RE: recent slowdown in routing table growth

[Iljitsch van Beijnum <iljitsch@muada.com>]

On Thu, 9 Jan 2003, Ayyasamy, Senthilkumar  (UMKC-Student) wrote:

> But,as per geoff's presentation, multi-homing/TE will surely
> 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.
> I think, prefix filtering contributed the most to the present
> 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.