Multihoming experiment

[Iljitsch van Beijnum <iljitsch@muada.com>]

A few observations on Christian and David's multihoming experiment:

This means source address dependent routing, but I don't think this 
term is used anywhere. The consequence of this is that sites that 
implement this CANNOT use any form of dynamic routing. Also, I'm afraid 
there will be traffic engineering problems because of RFC 3484 for 
hosts that implement this. For instance, if at some point the RIRs use 
up 2001::/16 and they start giving out address space from 2003::/16, a 
host with a 2001:: and a 2003:: address will use the router that 
announces the 2001:: prefix for all traffic to 2001::/16 which would be 
nearly all of the IPv6 internet.

And note well, from RFC 3484:

   Well-behaved applications SHOULD iterate through the list of
   addresses returned from getaddrinfo() until they find a working
   address.

Applications that don't implement this will have to wait for a prefix 
to become deprecated to switch to the other one, so the multihoming 
benefits for those applications would be even smaller.