[arin-ppml] Utilization policy is not aggregate

Jimmy Hess mysidia at gmail.com
Sat Nov 17 12:07:56 EST 2012

On 11/16/12, Larry Ash <lar at mwtcorp.net> wrote:
> Reaching 80% on a smaller allocation is a lot
> harder than a /18. Over time holes develop in the utilization.
> You will reuse them but at any given time it's difficult if not
> impossible.
> How about 80% overall with no single allocation under 70% (whatever).
OK....  that solves that particular problem.

Although, still... the  20%  criterion  is really there to give
applicants time to request new IPs before their existing resources are
exhausted;   I would say that  "allowing holes"  would be an
unintended side effect of the policy.

How exactly do we come up with the 80% rule in the first place, and
how exactly do we prove that 80% is the right number, and not  90% or

Instead of looking at the size of the allocation, and the number of
IPs used, perhaps policy for ISPs should look at the size of the
allocation,  and the _average size of a suballocation_  of each size
from  /32  down to the length of the block assigned.

                       Total average number allocated  per 12 month period
/32                   0
/31                   0
/30                   0
/29                   10
/28                   5
/27                   3
/26                   2
/25                   4
/24                   1

And state,  that  new resources may be assigned when any of these
conditions are true:

 (i)    Of all IPv4 resources previously received,  99% have been suballocated.

 (ii)    The number   of   unallocated IP addresses   sums to a number less than
         or equal to the  number of IP addresses allocated over the
previous 6 month period.

 (iii)  The ISP organization can show,   that when the ISP makes
allocations  for the next 3
       months,   it is not possible to map their existing unallocated
address space, onto
       each of those allocations,  without  renumbering customers,

       Or reducing  the available aggregate IP addresses that can be
allocated below
       the size of that ISP's average allocation,  times the average 3
months' number of allocations of that size.

> The 80% policy has always greatly favored the big guys. It's much
> easier to reach 80% on a /18 than a /20. Natural holes that occur
> always seem to amount to almost 10-25% in a /20 unless much of it
> has been delegated as /23's or /24's.


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