Subject: RE: recent slowdown in routing table growth

From: "Ayyasamy, Senthilkumar (UMKC-Student)" <[email-masked]>
Date: Thu, 9 Jan 2003 17:23:08 -0600

>  1) raised awareness: this exponentially-looking growth raised some
> alarms, there was a presentation in IETF51 in London (Aug 
> 2001), etc. --
> (some)  people fixed some of their systems.

> Mainly 1), but I'd also like to get some more concrete references.

http://www.potaroo.net/papers/bgp/bgp-june02.pdf
http://www.packetdesign.net/docs/cengiz.pdf

Major reasons for the dip in growth:
-  reduced number of specific entries due to awareness 
   based on CIDR report.
-  Use of prefix length route-filtering

But,as per geoff's presentation, multi-homing/TE will surely
be a major contributor in future.

 Also, see slide 10-12 in cengiz's presentation on the exact 
break down for the contributing factors in multi-homing.
It is good to hear that misconfigurations/multi-homing by means 
of MOAS is decreasing. Although, MOAS is an operational
technique, people do engineer them purposely/accidently.

One can check geoff huston BGP page for an up-to-date report.
Also, compare the above presentations with the previous IETF 
ptomaine/plenary presentations. 

I think, prefix filtering contributed the most to the present 
reduction in growth (refer randy's presentation-51th IETF)

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From: Iljitsch van Beijnum <[email-masked]>
Date: Fri, 10 Jan 2003 01:10:22 +0100 (CET)

> be a major contributor in future.

Why do people keep blaming multihomers for the mess that is the global
routing table? Based on what we can see today, this is utter nonsense.
There are maybe 10000 multihomers in the world. Even if they all do
traffic engineering that's 20k routes, out of the 110k we see today. The
absolute number one top reason for routing table pollution is stupidity.
I came very close to including a routing table dump for AS7843. That's
610 routes, which is insane by any account.

There are more than 50 ASes that announce more than 100 unnecessary
prefixes, for a total of around 10% of the routing table. This is
nothing less than criminal. See http://www.mcvax.org/~jhma/routing/all2.html

Then there are the address conservation policies, which make the RIRs
assign small blocks time and time again to people that are burning
through IP addresses like a forrest fire.

Routing table size problems because of multihoming are simply impossible
because of the 16 bit AS number space and the current IPv6 routing
guidelines that forbid multihoming.

You might as well blame Coca Cola for global warming because of the
carbon dioxide that escapes from their soft drinks. That makes more
sense than blaming multihomers for the routing table size.
> reduction in growth (refer randy's presentation-51th IETF)

Prefix filtering is evil because it targets the wrong people:
multihomers. De-peering that top 50 list will do much more good.

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From: "Christian de Larrinaga" <[email-masked]>
Date: Fri, 10 Jan 2003 10:14:00 -0000

I put Geoff's presentation at the master lectures up at
http://www.england.isoc.org/event/melectures.rhtm

If there is anybody in London on evening of Thursday 16th Jan the UK IPv6
Task Force is holding a lecture night and reception see
http://www.uk.ipv6tf.org for registration.

> http://www.packetdesign.net/docs/cengiz.pdf

snip
> ptomaine/plenary presentations.

Christian