ARIN IP6 policy for those with legacy IP4 Space

Dan White dwhite at
Thu Apr 8 18:05:09 CDT 2010

On 08/04/10 18:00 +0000, bmanning at wrote:
>On Thu, Apr 08, 2010 at 12:50:26PM -0500, Dan White wrote:
>> On 08/04/10 17:17 +0000, bmanning at wrote:
>> >	in the IPv4 space, it was common to have a min allocation size of 
>> >	a /20 ... or 4,096 addresses ... and yet this amnt of space was
>> >	allocated to someone who only needed to address "3 servers"... say
>> >	six total out of a pool of four thousand ninty six.  
>> Granted, that may have been the case many years ago.
>> However, this was not our experience when we obtained addresses, and the
>> ARIN rules as I understand them would not allow such an allocation today.
>	i picked a fairly recent example - the min allocation
>	size has fluctuated over time.  still it is not the case
>	that most folks will get -exactly- what they need - they 
>	will - in nearly every case - get more address space than
>	they need - due to the min allocation rules

We did, on our first allocation. We were well over 90% utilization and when
we asked our upstream ISP for more addresses, we were informed they would
not provide us a 17th /24. We scrambled to get our documentation together
for ARIN. We had to show efficient use of those 16 /24s, and we had to
document our immediate (12-24 month) need for addresses to get them.

>> >	Thats a huge amnt of wasted space.  If our wise and pragmatic leaders
>> >	(drc, jc, are correct, then IPv4 will be around for a very
>> >	long time.
>> >
>> >	What, if any, plan exists to improve the utilization density of the
>> >	existant IPv4 pool?  
>> I believe your question is based on an outdated assumption.
>	and that outdated assumption is?

The assumption that ARIN allocations are based on anything other than 12-24
month need (with only a few exceptions).

If there are a significant number of sparse allocations of IPv4 blocks in
ARIN, then that's a good indication that allocation rules need to be

Dan White

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