host-identifier with IPv6

Glen R. J. Neff neff_glen at
Fri Feb 27 20:07:08 UTC 2009

On Fri, 2009-02-27 at 13:15 -0500, Frank Sweetser wrote:

> I fail to see how simply making the numbers bigger should require any
> additional complexity, just additional diskspace and memory.

It's not just making the numbers bigger.  It's going from four small
value integers delimited by periods to potentially 32 digits of
hexidecimal values.  If you get hexidecimal, that's great, but the vast
majority of users and/or system administrators simply do not.  The
potential for a typo and the complexity in memorizing these addresses is
significantly greater.  My aim is to have it so no one buy the guy
setting up the router or the DNS server should never need to plug-in an
IP address - so that people don't need to think about it.

> Plug-n-play sounds great, except that in this case the "play" tends to end up
> being "hide and seek" as the hapless admin (network or system, take your pick)
> tries to go through IP/DUID/which host mappings looking for a misbehaving, or
> just missing, host.

> With a pure DUID system, generated randomly at boot time, there's no longer
> any consistent seed that can start the lookup chain required for a machine to
> automatically configure itself.  This means that the only choice left is to
> slowly, manually, and painstakingly pick the machine identity out by hand -
> not something very nice to any of your administrators.

"Those who say it cannot be done should not interrupt those who are
doing it."
      -- Chinese Proverb


 * Glen R. J. Neff
 * RTP TSG Network Team
 * neff_glen at
 * EMC^2 == E^2

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