Re: [rrg] IPv4 & IPv6 routing scaling problems

[[e-mail]]

 
In einer eMail vom 14.02.2010 17:00:37 Westeuropäische Normalzeit schreibt  
[e-mail]:

Hi,

I've only just stumbled across your TARA stuff, and am  reading 
through your mails. Re "Forget DV!", and double-plus to  that!


Well, then try to convince me while viewing the following:
I was told that an average route  contains about 20 hops. Imagine a  
chessboard like grid however with 10x10 rows and columns instead of 8x8.  Imagine 
each DFZ-router has only 4 neighboring DFZ-routers (which is  certainly less 
than in reality).Imagine the ingress at the upper left corner and  the 
egress at the lower right corner. Then there are (20 over 10) = 20x19x...x11  / 
(1x2x3....x10) = 184 758 shortest paths in-between.
 
Consider that there are more than 10,000 egress DFZ-routers ! 184 756 times 
 10 000 = 1 847 560 000 shortest routes. However there are multitudes  
thereof, if you envisioned (loopfree of course) detours as well! And if you  
envisioned that DFZ routers have more than 4 neighbor nodes (BTW, can  anyone 
provide useful valid figures so that we can discuss density issues and  
aspects?)
 
What a nonsense of algorithm !!! DV is a holy cow from the early  90's!
 
Please convince me, why provisioning and managing all these routes would be 
 reasonable? 
Particularly, when you can do it without!  
 
Heiner