[arin-ppml] Policy Proposal: Predicable IPv4 Run Out by Prefix Size

Member Services info at arin.net
Mon Jun 8 15:10:38 EDT 2009

ARIN received the following policy proposal and is posting it to the
Public Policy Mailing List (PPML) in accordance with Policy Development

This proposal is in the first stage of the Policy Development Process.
ARIN staff will perform the Clarity and Understanding step. Staff does
not evaluate the proposal at this time, their goal is to make sure that
they understand the proposal and believe the community will as well.
Staff will report their results to the ARIN Advisory Council (AC) within
10 days.

The AC will review the proposal at their next regularly scheduled
meeting (if the period before the next regularly scheduled meeting is
less than 10 days, then the period may be extended to the subsequent
regularly scheduled meeting). The AC will decide how to utilize the
proposal and announce the decision to the PPML.

In the meantime, the AC invites everyone to comment on the proposal on
the PPML, particularly their support or non-support and the reasoning
behind their opinion. Such participation contributes to a thorough
vetting and provides important guidance to the AC in their deliberations.

The ARIN Policy Development Process can be found at:

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American Registry for Internet Numbers (ARIN)

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1. Policy Proposal: Predicable IPv4 Run Out by Prefix Size

2. Proposal Originator: David Farmer

3. Proposal Version: 1.0

4. Date: 8 June 2009

5. Proposal type: new

6. Policy term: permanent

7. Policy statement:

Create a new subsection in section 4 of the NRPM;

4.X Maximum Allocation or Assignment during and after Run-Out

When ARIN receives its last /8, by IANA implementing section, a
maximum allocation and assignment size will be put into effect.  The
maximum allocation or assignment will be the next whole CIDR prefix less
than or equal to one quarter (1/4) of the total unrestricted IPv4
resources available to ARIN for allocation or assignment at the time,
but no longer than the applicable minimum allocation or assignment.  All
other allocation and assignment rules, requirements, or procedures apply
in addition.

If this maximum allocation or assignment provides insufficient
resources, additional resources may be request after a three (3) month
waiting period.

This section (4.x) is applicable to allocations and assignments from
ARIN's unrestricted IPv4 resources only, and is explicitly not
applicable to resources received through Transfers to Specified
Recipients per section 8.3, or any other specially designated resources.

8. Rationale:

This proposal is intended to insure an equitable distribution of the
remaining unrestricted IPv4 number resources available to ARIN once such
resources are no longer abundantly available from IANA.  Equity is
achieved by insuring the available resources are spread among multiple
entities and that no single entity may monopolize all of the resources
available through a single request, at least until the maximum equals
the minimum allocation or assignment size.

Reducing the maximum allocation or assignment size in proportion to the
amount of resources available should minimize, or possibly eliminate,
the need to fulfill requests with multiple smaller blocks.

Beyond providing predictability and order during the run out phase, this
proposal provides an equitable means of distribution of resources if or
when additional resources become available after ARIN has initially
exhausted such resources.  Such as if resources are returned, recovered
by other means, or further resources are obtained from IANA.

Other ratios, such as one half (1/2) or one eighth (1/8) could be
considered.  One eighth (1/8) would provide greater assurance of
eliminating the need to use multiple blocks to fulfill requests and
insure a greater number of entities receive resources.  However, one
eighth (1/8) is more likely to be seen as rationing and an attempt to
artificially extend the lifetime of IPv4.  During the ARIN XXIII policy
discussion there seemed to be a consensus that attempts to extend the
lifetime IPv4 resources would be undesirable.  While on the other hand,
one half (1/2) is less likely to ration the resources, it would likely
result in the resource being spread across significantly fewer entities
and increase the need to use multiple blocks to fulfill requests.
Therefore, the ratio one quarter (1/4) is proposed as a compromise
between competing sets of goals.

9. Timetable for implementation:  Immediate

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