Re: IP network address assignments/allocations information?

[Bill Sommerfeld <sommerfeld at orchard.arlington.ma.us>]

> if multiple addresses are available for a host, the chances are good 
> that the paths associated with some of those addresses are significantly
> better, or worse, than others.  with IPv4 multihoming, the routing system 
> sorts out which path to use.  this doesn't work perfectly but at least 
> the decision is made in light of some information about the nature and 
> current state of those paths.  with IPv6 multihoming, the sending host is 
> just guessing.  it's difficult to believe that this will work well.

That's why you add some feedback-based smarts to the address-order
selection scheme, and overlap the connection attempts (perhaps
separating them by an RTT or so).  Given typical distributed apps,
feedback selection based on end-to-end latency will be the right
answer in almost all cases; bandwidth-based feedback can also
potentially be done.

Given how hard it is to get an ISP do to anything special for you
these days, I really can't see a routing-system-based multihoming
actually scale down to, say, individual SOHO networks being
multihomed, while multiple-address-based multihoming doesn't require
anything special out of the ISP's..

					- Bill