Minimum globally routable address space?

Tue Feb 20 19:14:42 UTC 2001

If you're going to get a /20, I'd say get your own from ARIN.  The biggest
pain of a routing policy I've had to deal with (as far as other people's
policies go) is Verio, who only accepts /20 and greater for all of the
recently opened legacy class A networks (64., 65., 66 etc)

As long as you don't try to slice and dice your /20's into more specific
blocks to come out of other places, you'll be fine. 

Paul

-----Original Message-----
From: Dan Streufert [mailto:dans at icss.com]
Sent: Tuesday, February 20, 2001 1:34 PM
To: nanog at merit.edu
Subject: Minimum globally routable address space?

I am writing from a small, multi-homed ISP.  We are contemplating
terminating our relationship with one of our providers, and will need to
replace that non-portable space.
We are debating between getting a /20 from ARIN (we have justifiable usage)
or a /20 from our other provider.

On one hand, portability would be nice.  On the other, is a /20 globally
routable in practice? I seem to remember hearing that /19 was the smallest
that would not be filtered by anyone.

If anyone knows if there are filters for /20s out there, I would be
interested to know who filters them.

		Thanks,
		Dan Streufert