Private use of non-RFC1918 IP space

Måns Nilsson mansaxel at
Mon Feb 2 22:09:42 UTC 2009

--On måndag, måndag 2 feb 2009 16.15.06 -0200 Andre Sencioles Vitorio
Oliveira <asenci at> wrote:

> What about this?
> Genius from company A chooses public IP block A.
> Genius from company B chooses public IP block A.
> Genius collision detected...

What you do is go to your LIR and ask for a /24 and tell them "I am going
to use this for <purpose> which is at best semi-internal". It has worked
for me; I got a PI /24 for the facility management system in a datacenter.
(MODBUS over IP stuff, windows machines and embedded boxes sending email
alarms about burning UPSes and sauna-hot computer rooms) 

My colleagues argued that "this network won't ever be connected to
anything" but it took all of one week before they were proved wrong and the
first contractor VPN box was installed. QED.

The really, really, nice thing with registered PI or PA space is that it is
pretty unique, bar fatfingering and route hijacking. Once there is a
merger, the company with a RIPE db entry for the nonrouted space will have
a most convincing position in merger negotiations: "This is our space:
_you_ will renumber."

Burning v4 space is good. Gets us v6 faster. 
Måns Nilsson			M A C H I N A

HUGH BEAUMONT died in 1982!!
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