Re: OT: prefix length used by backbone routers

["Kastenholz, Frank" <FKastenholz@unispherenetworks.com>]

At 02:21 PM 8/10/01 +0859, Masataka Ohta wrote:
>Randy;
>
>> are you asking if the forwarding look-up is longest match on 64 or 128 bits?
>> i think the latter is mandatory.  we do allow allocation of /128s.
>
>Can't backbone routers assume 48 bit look-up for best effort unicast
>forwarding?

no

>Though who want to sell value-added (such as MPLS) routers may
>disagree, it is important for low-cost high-speed Internet.


that would be nice. 
but the cost of being able to do long (/32 and /128) lookups
is in the noise compared to the costs of all the other stuff, 
such as the somewhat shorter lookups (eg /24 or /48), high
speed optics (lasers etc), buffer memories, internal
switch fabrics, boards, and so on. 

Frank Kastenholz