In einer eMail vom 11.12.2008 23:11:52 Westeuropäische Normalzeit schreibt  
[email protected]:

On Thu,  Dec 11, 2008 at 3:42 PM,  <[email protected]> wrote:
>  Some comment and proposals to improve the strategy C text which  currently
> is:

This references  http://bill.herrin.us/network/rrgarchitectures.html

The current text  is:

> Suppress distant routes by aggregating them into sets expected  to be
> available in a given direction. Because LOC reachability info is  not
> flooded, the routing tables each router must deal with are  relatively 
small.
You should say, because user reachability information is not  flooded,..




>  --------------------------proposed text:
>  Extend BGP such that routers can acquire the view of a well-sparsed  
internet
> topology
> with strict links in the near surrounding  and - in general - with loose and
> looser links the
> more remote  they are (strict links to very remote nodes may still be part 
of
> this  topology). Determine the next best hop  based on that viewed
>  destination node which is either the true destination node or a node  which
> is closest to  the true but not yet visible   destination node. Arrange the
> results such that a best next hop can be  retrieved either by 1 or by  3
> table lookups.

As I  mentioned in our email exchange, I don't understand what this
means. What  is a "well-sparsed" Internet? 
A topology which doesn't show the details of the remote  network  parts. 
Similar to routing from NY, Broadway to Sausolito, Main Street without  seeing 
the 
Main-Street prior entering Sausilito itself.
 

What is  a loose or strict
link? 
This is IETF terminology.

How do  you determine that a node is "closest to" a node that
isn't visible? 
By the distance (in miles or km) which is adequate in location base routing  
- IMO.

What is  the significance of 1 or 3 table lookups?
Much faster forwarding. Eliminating the need for caching.




> Of course, incremental deployment has to be  supported.The goal is to shrink
> the routing table continuously so that  it becomes empty as soon as  all DFZ
> routers will  comply.

This is a goal, not a strategy.
I skipped the previous explanatory sentence because I thought it is too  hard 
to understand :-(
 
I have one further comment with respect to the mentioned economic model of  
IP. It is just the opposite:
Strategy C avoids everything which looks like administrative hierarchy.  
Rather ask ILNP or HAIR or Joel's presentation. There is no single hint for any 
 
political/administrative influence in all of what I presented.
Another point: I have always argued against the generalization that  
hierarchical routing is doomed to cause stretch=3 because it is not true wrt  
TARA. 
However I can well understand that this reproach is appropriate to ALL the  
currently arising hierarchical ideas.  
 
Heiner
 
 
 
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