In einer eMail vom 21.03.2008 01:54:56 Westeuropäische Normalzeit schreibt  
[EMAIL PROTECTED]:

>  quote from draft-carpenter-idloc-map-cons-01.txt:
> 4.6.   Scale
>  
>    We want no arbitrary scaling  limits.  However, proposed  scaling
> targets are 10 to 100  billion Stacks (which scales the  Identifier
> Namespace), and 10  million sites.  Although the  latter does not
> directly scale  the Internet's Locator Namespace,  it indicates the
> worst-case  granularity of the routing table for  that Locator
>  Namespace.  If we don't do better than random  allocation of  address
> blocks to sites, we will end up with 10  million routing  table
> entries.

These weren't consensus numbers. Since then,  Tony has convinced me
that we need to allow mapping down to individual  hosts as well
as aggregates (so my answer to his question is Yes), but we  probably
need to increase the likely size of the map from 10 million
to  100 million. I think these changes are compatible, but note my
belief that  aggregates as small as a SOHO network would be
very rare in the map. Others  disagree, and that changes the
numbers substantially.

Brian



10 millions, 100 millions and even billions - these figures wouldn't  
frighten me  because the only right solution is the one that scales  
logarithmically. 
My solution would not only shrink the table size  and update churn, but 
consequently also the work load per router.  Hence it could take advantage of 
the 
idle time, e.g. by pursueing  similar goals like  the rtgwg wrt. to multipath 
and detours.
 
Quote------------
 
> Doesn't the issue persist independent of the characteristics based  on
> which a path gets selected?  Independent of *how* a path gets  selected,
> you need to decide *who* selects it (or who selects which part  of it).

Well, that's true of course. But nothing  can change the fact
that the originating host chooses  the source address and destination
address that the  packet starts out with, and all subsequent  choices
depend on  that.

Brian
End of  quote -----------------
 
Example: Be that the destination is "just behind the globe". So you may  have 
a West-route, a North-, East- and  South-route. The ingress may  take a 
choice and yes, all subsequent choices may not only depend on that but  should 
also 
COMPLY with that !!!! Sure, some respective assignment may have  to be 
conveyed, but first of all be enabled ! Multihoming ist just the last  hop of 
the 
West-,..,South-route issue.
 
------
There are  more issues which have never been discussed  here:
Support of (better models of) multicast, mp2mp ! 
The irrational behind using orthogonal models for intra/inter-domain  routing.
The fundamental deficiencies of distance vector.
 
------
Incremental deployability:
Like "ships in the night", as has been mentioned, several mechanisms may  
coexist:
Seafarers used to watch the stars. Using the compass and watching the  
magnetic needle came in parallel.
Car navigation did not start out with CDs that covered the entire continent  
either.
All of these methods are independend from each other, can evolve, and also,  
may fallback if necessary.
My solution was argued down to be not incrementally deployable. Just the  
opposite is the case and can be compared with the  progress in automobile 
navigation where at first the navigation  quality was also minor (e.g. was lost 
itself), so that more often  the driver had to fallback using other methods 
(maps, 
direction  signs).  
Here,  at the beginning when a rather small number of routers  takes part in 
the new protocol, switching back to the current method will be  necessary 
although the packet hasn't yet approached the destination very well.  But that 
will be improved the more routers are going to participate. In a  half-half 
scenario, falling back to current BGP however means, to benefit just  from the 
REGIONAL update churn! The global update churn is only required  for today's 
routing.
 
Yes, a new additional mechanism gets its deployment incentives from  
providing better service (the compass needle can be watched also in cloudy  
nights, 
the car navigation makes driving comfortable,..)
I mentioned quite a few such additional aspects above. There are even  more 
(e.g. there is really no IPv4 depletion problem) and I learn more and  more the 
longer I follow this mailinglist discussion.
 
Heiner
 
 
 
 
 
 
 
 
 
 
 
 
 
extremely, it would hereb small. There is no prefix aggregation  problem if 
you aggregate the area instead (remember:Rhekther's law offers 2  alternative 
choices).
 
 
 
I have heard that a Dijkstra can be already be run within a second   dealing 
with 10 000 nodes.
 
 
 
 



   

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