Consultation - Retirement of IPv4 Countdown Plan

Posted: Monday, 21 March 2016

In 2011, ARIN published IPv4 countdown procedures to ensure fair and equitable administrative processing of IPv4 requests leading up to the IPv4 depletion event. These countdown procedures have been meticulously followed for the past five years. We have been inside the 4th and final phase of this plan since April of 2014 when ARIN reached one remaining /8 equivalent. This final phase of the plan includes the processing of all IPv4 requests on a "first in, first out" basis (chronologically based on time stamp) and team review for all IPv4 requests, regardless of size. 

You can find the processing procedures for each phase on ARIN's IPv4 Countdown Plan page at the ARIN public website.

ARIN's IPv4 free pool depleted in September of 2015. Even though the depletion event has already occurred, ARIN staff continues to apply Phase 4 countdown procedures to IPv4 free pool requests today. With the exception of requests that fall under NRPM 4.4 (micro-allocations) and 4.10 (dedicated IPv4 block to facilitate IPv6 deployment), all IPv4 requests that qualify for an allocation/assignment are destined for the Waiting List for Unmet Requests. Since the waiting list started in 2015, over 300 organizations have been added. As the waiting list continues to grow, there is diminishing likelihood new additions will receive IPv4 blocks resulting from returns or IANA distributions in the coming years.

ARIN staff is considering the retirement of the IPv4 Countdown Plan. This would involve the cessation of Phase 4 processing procedures in our future review of IPv4 requests that are destined for the waiting list for unmet requests. IPv4 request tickets would continue to be responded to in generally the same number of days across the many different open requests, but would no longer be processed on a strict "first in, first out" basis. We would also discontinue the team review requirement for IPv4 request tickets. Removing these procedures would allow the recovered staff time to be redirected to other registration related work activities inside the ARIN Registration Services Department, such as handling the increasing number of transfers.

We seek your comment on the possible retirement of ARIN's IPv4 Countdown Plan.

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This consultation period will close at 5:00 PM EDT, 22 April 2016. Please contact us at if you have any questions.