[ppml] [narten at us.ibm.com: PI addressing in IPv6 advances in ARIN]

[David Conrad]

Chris,

This is really not ppml related, so this'll be my last post on the  
topic.  If you'd like to explore the ideas more, I'm happy to privately.

> So, either the community says: "no ipv6 until multihoming is 'solved'"
> or we suck it up and start deploying with PI space for the sake of
> deployment of v6. I'm not convinced that routing PI space will be
> 'short lived'...

Agreed, but maybe it doesn't matter...

> 'middlebox' means 'nat host'...

Middlebox means "box in the middle" to me.  If I used the wrong  
terminology, excuse me.

If I rewrite the IP header of a packet when it traverses the source  
edge/core boundary into more easily routed gibberish, would anyone  
care _if I guarantee that the gibberish is rewritten to the original  
IP header contents at the destination core/edge boundary_?

Yes, it is explicitly NAT.  The end point identifier's upper 48 (or  
whatever) bits is being "network address translated" into the routing  
locator (the lower 80 bits would be untouched).  But to avoid the  
soul-searing EVIL (plain and simple, from beyond the 8th dimension)  
of NAT, you simply reverse the translation, restoring the upper 48  
bits (which, conveniently, don't have to be carried around in the  
packet since the destination is pretty much guaranteed to know what  
end point identifier prefix it is at).  The two EVILs cancel each  
other out.  The hard part is doing the lookup of the routing locator  
given the end point identifier at the source edge/core boundary (but  
I'd argue that's a distributed lookup problem that can be and has  
been solved a number of ways).

>> (I'm not smart enough to figure out how the geotopo approach would
>> work without causing a return to the equivalent of the pre-1994
>> international telephony settlements regime, but that's my own lack of
>> imagination I suspect).
> I'm with you on that, I see telco settlements as the 'only'  
> solution to this...

And I don't really think the folks who fought to kill it the first  
time would be excited to see it rise zombie-like from the grave.  But  
maybe that's just me. I know folks in Geneva and in monopoly PTTs all  
over the world would be happy...

Rgds,
-drc
--------
My opinions are my own and do not necessarily represent the
opinions of any organization I may be a part of.  So there.