Internet Edge Router replacement - IPv6 route tablesizeconsiderations

Leo Bicknell bicknell at
Fri Mar 11 13:55:05 CST 2011

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 at - CCIE 3440
        PGP keys at
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