RE: draft-kurtis-multihoming-longprefix comments

["Tony Li" <Tony.Li@procket.com>]

|   I bring it up because it is not significantly different than other
|   mapping schemes that have been proposed. We know it doesn't 
|   scale, and
|   it is only done once at call setup rather than per packet.


Correct.  And in some cases, it seems that folks are getting paid
for the feature.


|   > Yes, they both do.  People still don't like 'em cause they're 
|   > "not the IP way."
|   
|   If by 'IP way' you mean that it is a change to the expectations apps
|   have of the underlying architecture, then I have to agree. It is not
|   clear to me that 16+16 is visible to apps, so maybe that 
|   doesn't apply.


16+16 would be very visible to the apps.  In fact, any change that has
independent identifiers and locators would be a change to the apps.  Because they
are not expecting/allowing that.


|   You seem to think I am being obstructionist. I am not.


Then please educate me on your position.  What scalable, implementable
solution do you advocate?


|   And when I am in Japan connecting to home, topological 
|   detail of Seattle
|   has absolutely nothing to do with which service provider I 
|   hand packets
|   to. The fact the destination is Seattle rather than San 
|   Francisco might
|   have something to do with a trans-pacific cable choice, but 
|   the cable &
|   dsl providers are present in both so PA doesn't really help with TE
|   there. Once the radius is reduced to 1000km, the number of 
|   possibilities
|   increases dramatically, but outside that range there are 
|   really very few
|   choices. Why should all DFZ routers outside that range know 
|   the details?


You're suggesting abstraction that grows with distance.  You may
recall that I proposed that we do exactly this in 1992 with continental
aggregation.  I was shouted down.

This only works because in almost all cases, continents are internally
connected and the number of exceptions is quite small.  Further, over
time, as we wire the planet, even these exceptions will disappear.

So yes, I have no objections to continental scale aggregation.  
Unfortunately, that is not a technique that recurses down to the 
micro level.  We need to work with the connectivity that is naturally
in place and cannot force fit it to suit.

To take your street address metaphor farther, we should not insist
on building bridges across the Grand Canyon just to insure that a
zip code is contiguous.

Tony