The stupidity of trying to "fix" DHCPv6

Leo Bicknell bicknell at
Tue Jun 14 00:54:53 UTC 2011

In a message written on Mon, Jun 13, 2011 at 05:41:12PM -0700, Owen DeLong wrote:
> > The IPv4 host does this once and gets its lease. If there is no DHCPv6 server then DHCPv6 clients would keep broadcasting forever. Not a good thing.
> > 
> Which is no worse than the behavior of an IPv4 host on a network without a DHCP server.

I understand on some level why the IETF doesn't want DHCPv4 to be
able to hand out IPv6 stuff, and doesn't want DHCPv6 to hand out
IPv4 stuff.  In the long run if you assume we transition to IPv6
and run only IPv6 for years after that it makes sense.

However, I do think a single option is needed in both,
"ProtocolsAvailable".  Today it could have "4" or "6", or "4,6".
In the future, who knows.  The idea being if I am a dual stacked
host and I do DHCPv4 and get back that only 4 is available, I might
stop doing DHCPv6 or at least make my exponential backoff even more
exponential.  Similarly, if I get back "4,6", I might know to
immediately try the other protocol as well.

This would allow end stations to greatly optimize their behavior at all
stages of deployment.

       Leo Bicknell - bicknell at - CCIE 3440
        PGP keys at
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