[63893] in North American Network Operators' Group
RE: BellSouth prefix deaggregation (was: as6198 aggregation event)
daemon@ATHENA.MIT.EDU (McBurnett, Jim)
Sun Oct 12 15:08:38 2003
Date: Sun, 12 Oct 2003 15:07:46 -0400
From: "McBurnett, Jim" <jmcburnett@msmgmt.com>
To: "Haesu" <haesu@towardex.com>,
"Jared Mauch" <jared@puck.Nether.net>, <nanog@MERIT.EDU>
Errors-To: owner-nanog-outgoing@merit.edu
>=20
> IMHO, I think we should create a route-set obj like call=20
> it... RS-DEAGGREGATES and list all the major irresponsible=20
> providers's specific /24's in it...
CASE: Business has a /24 from X provider in order to multihome.
That /24 is de-aggregated from a /19, with this policy that
/24 may not be routed.
possible exception: When 2002-3 get passed by ARIN, this could even take
on new meaning. ARIN says they will use a single /8 for the handing
out of /22-/24 for multihoming end users. will you then filter those=20
/24's also?
Also:
What happens when that /24 for Business Y noted above is dual routed
by ISP A and ISP B, and ISP A's upstream filters but ISP B's does not?
Will there be asymmetric routing?
Finally:=20
Can anyone from BellSouth, explain the end goal of the de-aggregation?
I suspect with 40 + ASs they may be rebuilding their network with a
recently announced list of new IP services and DSL growth as asked for
under the Federal government Rural DSL regulations... (I'm not trying =
to defend
them, just giving some possibilities)
> So some ASes who wish to not accept deaggregated specifics=20
> using RPSL can update their AS import policy to not import=20
> RS-DEAGGREGATES...
>=20
> Just my humble opinion.. Comments/critics welcome :)
>=20
> -hc
>=20
> --=20
> Haesu C.
> TowardEX Technologies, Inc.
> Consulting, colocation, web hosting, network design and implementation
> http://www.towardex.com | haesu@towardex.com
> Cell: (978)394-2867 | Office: (978)263-3399 Ext. 170
> Fax: (978)263-0033 | POC: HAESU-ARIN
>=20
>=20
> On Sun, Oct 12, 2003 at 11:26:49AM -0400, Jared Mauch wrote:
> >=20
> > On Sun, Oct 12, 2003 at 01:02:57PM +0000, Stephen J. Wilcox wrote:
> > >=20
> > > > Can anyone from BellSouth comment? What if a few other=20
> major ISPs were
> > > > to add a thousand or so deaggregated routes in a few=20
> weeks time? Would
> > > > there be a greater impact?
> > >=20
> > > one word - irresponsible
> >=20
> > This clearly stands out to me as a reason to keep and use
> > prefix filtering on peers to reduce the amount of junk in=20
> the routing
> > tables. If bellsouth needs to leak more specifics for load=20
> balancing
> > purposes, fine, just make sure those routes don't leave=20
> your upstreams
> > networks and waste router memory for the rest of us that=20
> don't need to
> > see it.
> >=20
> > - Jared
> >=20
> > > > (Note: The above numbers are based on data from=20
> cidr-report.org. Some
> > > > other looking glasses were also checked to see if=20
> cidr-report.org's view
> > > > of these AS's is consistent with the Internet as a=20
> whole. This appears
> > > > to be the case, but corrections are welcome.)
> > > >=20
> > > > -Terry
> > > >=20
> > > > > -----Original Message-----
> > > > > From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On=20
> > > > > Behalf Of Terry Baranski
> > > > > Sent: Sunday, October 05, 2003 3:01 PM
> > > > > To: 'James Cowie'; nanog@merit.edu
> > > > > Subject: RE: as6198 aggregation event
> > > > >=20
> > > > >=20
> > > > >=20
> > > > > James Cowie wrote:
> > > > >=20
> > > > > > On Friday, we noted with some interest the=20
> appearance of more=20
> > > > > > than six hundred deaggregated /24s into the global routing=20
> > > > > > tables. More unusually, they're still in there=20
> this morning. =20
> > > > > >=20
> > > > > > AS6198 (BellSouth Miami) seems to have been=20
> patiently injecting=20
> > > > > > them over the course of several hours, between=20
> about 04:00 GMT=20
> > > > > > and 08:00 GMT on Friday morning (3 Oct 2003). =20
> > > > >=20
> > > > > If you look at the 09/19 and 09/26 CIDR Reports,=20
> BellSouth Atlanta
> > > > > (AS6197) did something similar during this time=20
> period -- they added
> > > > > about 350 deaggregated prefixes, most if not all /24's. =20
> > > > >=20
> > > > > > Usually when we see deaggregations, they hit=20
> quickly and they
> > > > > > disappear quickly; nice sharp vertical jumps in the=20
> table size.
> > > > > > This event lasted for hours and, more importantly,=20
> the prefixes=20
> > > > > > haven't come back out again, an unusual pattern for=20
> a single-origin
> > > > > > change that effectively expanded global tables by=20
> half a percent.=20
> > > > >=20
> > > > > That AS6197's additions are still present isn't encouraging.
> > > > >=20
> > > > > -Terry
> > > > >=20
> > > >=20
> > > >=20
> >=20
> > --=20
> > Jared Mauch | pgp key available via finger from=20
> jared@puck.nether.net
> > clue++; | http://puck.nether.net/~jared/ My=20
> statements are only mine.
>=20
>=20
