Gordius has left the building. Was: RE: The Gorgon's Knot.

Alex Bligh alex at alex.org.uk
Wed Oct 3 08:53:52 UTC 2001




--On Tuesday, 02 October, 2001 11:09 PM -0400 "Bender, Andrew" 
<abender at taqua.com> wrote:

> We'll have to see another knee in route
> proliferation before this becomes a problem, and space exhaust would
> most certainly prevent this from happening.

Ah, but with what minimum prefix length:
a) Verio-esque
b) /24 - current 'global minimum filter length'
c) /32
d) A mixture between (a) and (b) - current situation

People need to recognize that there is defacto filtering going
on out there is everyone's network (well, nearly everyone's),
in that very few people accept longer routes than a /24. In
a CIDR world that's a different filtering rule to the Verio
one, but it's still arbitrary (in some senses - think non-RIR
assigned class A space - rather more arbitrary).

IE is the assumption space exhaust will precede the problems
you predict on router hardware precisely BECAUSE RIR allocation
rules (the more sensible ones), and the /various/ filtering,
dampening policies and the othr pro-aggregation work, has
determined a minimum useful prefix size? In which case getting
rid of the policies which make your assumption correct would
be a bad thing.

--
Alex Bligh
Personal Capacity.




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