In einer eMail vom 26.07.2008 16:22:28 Westeuropäische Normalzeit schreibt  
[EMAIL PROTECTED]:

The  document it was based on is still  at
http://www.cs.auckland.ac.nz/~brian/DFZng.pdf.
I would probably used  different terminology today; it certainly
isn't a worked-out  proposal.

Brian





Brian, 
Your draft reminds me of PNNI although your hierarchy is based on  BGP/DV and 
not OSPF/Dijkstra. 
PNNI's hierarchy  had to be in compliance with some particular AFI,  i.e. 
with prefixes from one of these 4 :Data Country Code, E.164,  designated 
numbering for enterprises, private numbering plan. Concurrently all  the 
remaining 3 
AFIs had to be serviced nevertheless as well.
 
Myself, I would have favored the hierarchy of your solution, if I  wouldn't 
have made progress meanwhile with respect to: getting rid of ALL  this prefix 
building stuff, getting rid of the need for configuration (who is  border node, 
who is peer group leader; a router wouldn't even need some  configurational 
data that indicated up to which hierarchical level it has to  deal with) - and 
finally getting rid of a fix hierarchy itself.
 
DV-based versus topology-aware:
Not long ago Lixia asked for comments regarding a draft which praised the  
map-encap's benefits for multipath. There is a proverb: The whole is more than  
the sum of its parts. Applied: The topology is more than all routes to all  
destination nodes. By knowing the topology all routes to some destination could 
 
be provided (including those which contain some crankback hops). But 
certainly  not, given today's BGP, where a router has no idea what happens 
(transitively)  with an UPDATE message it is forwarding. Also, a router does 
not inform a 
 neighbor about a worse route, if this neighbor has told him a better route. 
I.e. distance vector based solutions prevent perfect multipath  routing.
 
Heiner
 
 
 
 
 
 
 



   

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