[rrg] and while we're at it, here's a view from the ground...
HeinerHummel at aol.com
HeinerHummel at aol.com
Fri Oct 31 11:33:04 PDT 2008
In einer eMail vom 31.10.2008 17:13:09 Westeuropäische Normalzeit schreibt
darlewis at cisco.com:
> As a matter of fact this RRG group has never understood what
> is the REAL cause of the problem nor how to exploit location REALLY.
>
> Heiner
>
I guess its equally apparent you never understood that geo addressing
requires fundamental changes to the economic make up of the commercial Internet.
-Darrel
Oh no. The way I would use geographical coordinates is completely
transparent to any geographical meaning (like continent, country, state, city,...) It
is only a means to select the right "proxy destination node" in the case that
your true destination node is not yet "on your radar screen". Based on it
you determine the next hop. There is no change of the economic make up. It is
only that the next hop is determined in a different and scaling way and can,
in the data plane, be retrieved much faster than by searching thru a 300 000
entries sized table.
In a preceding email I once stated that the next hop determination (in the
data plane) takes only one single table offset lookup. Admitted, I have to
backup a little bit: If the destination is within a different spherical
rectangle (limited by two consecutive longitudes and two consecutive latitudes) yes
then it takes only 1 table offset lookup. However, otherwise it will take 3.
This wouldn't by any different even if the internet would be a million times
bigger.
And this would only be the beginning for better routing:
With respect to a particular destination any router can subdivide its
adjacent links into 3 classes A, B, C.
Class A: the remote node is one hop closer to the destination
Class B: the remote node is equidistant away from the destination
Class C: the remote node is one hop further away from the destination
Multipath: With DV-based routing you can only use the links of class A. With
TARA you can also use the links of classes B and C - which includes
detecting whether or not the link leads into a dead end area, and/or whether or not
there is a chance to wind up in a loop and how to avoid it if applicable.
Without TARA: In spite of 250 000 stored routes only one third of the
possibilities (i.e. only class A links) can be used. Note, the second best hop
may already be part of a detouring path, i.e. from class B or C !
BTW: The IETF's intra-domain routing isn't any better, see ipfrr :-(
Heiner
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