Provider/NAP filtering policies

Mon Sep 13 17:53:57 UTC 2004

My apologies, allow me to make a clarification.  When I mentioned NAPs,
I was referring more to provider peering policies _AT_ a NAP, rather
than a NAP's peering policies which of course as you pointed out would
be moot.

Being relegated to closed enterprise environments for the past few
years, I'm trying to play catch-up and validate my previous assumption
that most providers filter at a /19 boundary, etc.

Regards,
Jade

-----Original Message-----
From: Bill Woodcock [mailto:woody at pch.net] 
Sent: Monday, September 13, 2004 12:42 PM
To: Deane, Jade
Cc: nanog at merit.edu
Subject: Re: Provider/NAP filtering policies

      On Mon, 13 Sep 2004 JDeane at sungardfutures.com wrote:
    > I was hoping someone could point me in the direction of
provider/NAP
    > prefix filtering policies.  Most important to me is UU and Cogent,
but a
    > concise listing of notables would be much appreciated.

Just to clarify, NAPs or Internet exchanges are typically (like more
than 99% of the time) layer-2 services, which don't pay attention to or
care about layer-3 things like IP prefixes.  A few have policies
regarding what participants should filter on their own behalf, but of
the four hundered odd exchanges currently operating out there, I don't
know of any which filter prefixes themselves.

Virtually all _providers_ over a certain size filter heavily, of course,
and that's probably the portion of your question you'll get more (and
more
useful) answers to.

                                -Bill