RE: Filtering levels (was RE: multi-homing without the BGP (was RE: Packet Loss))

["Daniel Golding" <dan () netrail net>]

Jonathan,

It is not safe to assume that. Verio, amongst others, still filters at ARIN
allocation boundaries. Also, those trying to subnet old class B address
blocks, will have significant problems, even at the /17 level. If you have
upstream(s) willing to advertise aggregates for you, that's the best way to
handle this problem in a discontiguous network.

- Dan Golding
NetRail, Inc.

-----Original Message-----
From: owner-nanog () merit edu [mailto:owner-nanog () merit edu]On Behalf Of
Jonathan Disher
Sent: Friday, December 15, 2000 2:43 PM
To: nanog () merit edu
Subject: Filtering levels (was RE: multi-homing without the BGP (was RE:
Packet Loss))



On Fri, 15 Dec 2000, Daniel Golding wrote:

> advertise blocks smaller than a /20 to each other (/24 is a more normal
> filtering level these days). Also ensure that whichever of the upstreams

Is it safe to assume[*] that an announced /23 will not be filtered by any
major (or even the minor) backbones?  We just got our ARIN allocation (and
I won't go into that, the lag time was all my fault), and I'm currently
planning allocation for some remote offices and a couple of hosted
buildouts.  I'm hoping to not have to announce anything larger than a /23
from any one site unless necessary.

-j

[*] - It's never safe to assume anything internet related; relatively
speaking, is it safe...

-Jonathan Disher
-Systems and Network Engineer, Web Operations
-Internet Pictures Corporation, Palo Alto, CA
-[v] (650) 388-0497 | [p] (877) 446-9311 | [e] jdisher () eng ipix com