In a message written on Fri, Mar 11, 2011 at 10:58:09AM -0800, Leo Bicknell wrote:
That said, ND has built into it DAD - Duplicate Address Detection. There is already an expectation that there will be collisions, and the protocols to detect them are already in place. I see little to no reason you couldn't use a different length subnet (like the /96 in your example), randomly select an address and do DAD to see if it is in use. Indeed, this is pretty much how AppleTalk back in the day worked (with a 16 bit number space).
Three people have now mailed me privately saying that DAD does not provide a way to select a second address if your first choice is not in use. What I am basically suggesting is to use the same method in RFC 3041 as the default way to get an address. That is the protocol is already defined and deployed, it's just today it's used for a second (third, fourth, ...) address. -- Leo Bicknell - bicknell@ufp.org - CCIE 3440 PGP keys at http://www.ufp.org/~bicknell/