The Department of Work and Pensions, UK has an entire /8

George Herbert george.herbert at
Thu Sep 20 08:18:18 UTC 2012

On Sep 20, 2012, at 12:21 AM, joel jaeggli <joelja at> wrote:

> On 9/20/12 12:09 AM, George Herbert wrote:
>> On Sep 19, 2012, at 9:58 PM, Jimmy Hess <mysidia at> wrote:
>>> There is still no technical reason that 240/4  cannot be
>>> rehabilitated, other than continued immaterial objections to doing
>>> anything at all with 240/4,  and given the rate of IPv6 adoption thus
>>> far, if not for those,  it could possibly be reopened as unicast IPv4,
>>> and be well-supported by new equipment, before the percentage of
>>> IPv6-enabled network activity reaches a double digit percentage...
>> Excellent idea.  Now build a time machine, go back to 2005, and start work.
> Sorry it was a bad idea then, it's  still a bad idea.

Bad Idea or not, stopgap or not, it was and remains technically, programmatically, and politically feasible.

The critical failure is that starting RIGHT NOW would deliver five years-ish too late, which renders it a moot point.  In two or three years we may well regret not having done it in 2005; in seven years we will have had to have solved and deployed IPv6 successfully anyways.

We could have started it at a more opportune time in the past.  We could also have done other things like a straight IPv4-48 or IPv4-64, without the other protocol suite foo that's delayed IPv6 rollout.  Operators could have either used larger baseball bats or more participating numbers to make some IPv6 protocol design go the other way.  IETF could have realized they were in Epic Fail by Too Clever territory.

All of these things are water under the bridge now.  We have what we have.  It being amusing to grouse about mistakes of the past does not magically change the present.  We have rapidly vanishing IPv4 and no 240/4, IPv6, and no time.  That is reality.

Pining for 240/4 fjords is not a time machine to change the past.

George William Herbert
Sent from my iPhone

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