[29423] in North American Network Operators' Group
Re: using IRR tools for BGP route filtering
daemon@ATHENA.MIT.EDU (John Fraizer)
Thu Jun 22 16:08:22 2000
Date: Thu, 22 Jun 2000 16:05:54 -0400 (EDT)
From: John Fraizer <nanog@EnterZone.Net>
To: Danny McPherson <danny@tcb.net>
Cc: nanog@merit.edu
In-Reply-To: <200006221914.NAA09567@tcb.net>
Message-ID: <Pine.LNX.3.96.1000622155754.10626A-100000@Overkill.EnterZone.Net>
MIME-Version: 1.0
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Errors-To: owner-nanog-outgoing@merit.edu
I agree totally with prefix-list filtering customers and we have done so
from the very beginning. (Who wants to blemish the reputation of their
ASN as result of a customer being a bonehead and announcing default, etc?)
Provider<->Provider prefix-list filtering becomes much more involved
however. When a provider has 400+ bilateral peering relationships, the
time it takes to bring a new customer online who has their own address
space grows substantially. It is no different when a provider obtains
additional address space. If their peers are prefix-list filtering, they
have to contact every peer to have them blast a hole in the filters for
the new address block.
In a perfect world, we would not need to filter, period. Filtering
customers has become necessary to survival. I see Provider<->Provider
filtering as a major hurdle to jump anytime your (or anyone elses) network
expands in relation to prefixes being legitimately announced.
---
John Fraizer
EnterZone, Inc
On Thu, 22 Jun 2000, Danny McPherson wrote:
>
>
> I agree with this, and have seen the document, and have worked for
> large providers that performed prefix filtering on customers long
> before IOPS existed.
>
> However, if every ISP performed prefix-based filtering between one
> another, it'd be improved "a lot more". I recall more than a few
> instances when providers inadvertently broke other providers customers
> by "mis-advertising" prefixes.
>
> And if every ISP performed SA verification between one another
> (presumably with the same filters) it would again be improved "a
> lot" more.
>
> -danny
>
> > If every ISP does prefix based filtering on its
> > downstream customers, the integrity of the Internet
> > routing system will be improved a lot. The document
> > below proposes such a model:
> >
> > http://www.iops.org/Documents/routing.html
>
>
