How to force rapid ipv6 adoption

Matthew Newton mcn4 at
Fri Oct 2 10:58:51 UTC 2015

On Thu, Oct 01, 2015 at 05:58:59PM -0700, Owen DeLong wrote:
> Still, Todd, ignoring the other parts, the least you can do is
> answer this simple question:
> How would you implement a 128-bit address that is backwards
> compatible with existing IPv4 hosts requiring no software
> modification on those hosts? Details matter here. Handwaving
> about ASN32 doesn’t cut it.

It was a semi-serious question, hence the smiley. I'd be genuinely
interested if there is a sensible way to do the above. I can't
think of one.

Sometimes you just have to say something is broken and start
again. I think fitting 128 bit addresses into something only
designed for 32 bit is one of those. The resulting enchancement is
likely to be such a cludge that we'd be moaning about it for
decades to come, and would still require everything to be upgraded
(e.g. router ASICs that only look at 32 bits), so why not upgrade
to something cleanly designed from the start?

There's much wrong with IPv6 as well, but it's a shedload nicer
than a hack on something not designed to support it.

I've run IPv6 on my home network for over 10 years. It's not hard.
The only real reason we've not done a bit rollout at work yet is
that there are always other things that take priority, not that
it's actually that difficult to do.


Matthew Newton, Ph.D. <mcn4 at>

Systems Specialist, Infrastructure Services,
I.T. Services, University of Leicester, Leicester LE1 7RH, United Kingdom

For IT help contact helpdesk extn. 2253, <ithelp at>

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