5 Misperceptions about ARIN IPv4 Depletion

5 Misperceptions about ARIN IPv4 Depletion

Leslie NobileBy Leslie Nobile, Director of Registration Services, ARIN

Last week, ARIN’s available IPv4 inventory hit the 1 /8 mark, kicking off the final phase of our IPv4 Countdown plan.  Since we made that announcement, we’ve seen some online buzz on news sites like: CNET, Network World, ZDNet, Enterprise Networking Planet, across blogs, forums, and social media.

There has been some animated discussion and speculation about ARIN’s IPv4 depletion, in various places ranging from forum discussions to Twitter haikus.  In much of the discussion about this news, we did find a few persistent misconceptions.  So we thought we would take the opportunity to clear up a few of these misconceptions, and provide some facts to help you better understand the situation.

1. ARIN has run out of IPv4 address space

Close, but not quite.  ARIN’s IPv4 inventory has reached a new low,  but we’re not out yet. ARIN’s available IPv4 inventory is published daily on our home page at www.arin.net. If you click on the Countdown plan, you can see a break out of the remaining IPv4 block sizes. The totals on the Countdown page don’t include space that has been reserved for specific purposes designated by policy, including the /10 of IPv4 space set aside to help facilitate IPv6 deployment and the /16 that has been set aside for micro-allocations.  Additionally, any space that is returned or revoked is held for a period of 60 days, so that space will not show up in the available inventory either.

2. ISPs and End-users can’t get IPv4 address space from ARIN anymore

Not true. ARIN is still assigning and allocating IPv4 space in accordance with policy, just like we have always done.  However, in the near future, it is quite probable that an organization may not be able to get the address block size they qualify for from ARIN, at which point they may choose to accept the largest block size available or be added to a waiting list for unmet requests. 

3. ARIN policy changed after reaching the final /8

False. Unlike some of the other Regional Internet Registries (RIRs), the ARIN community did not develop a policy that kicked in when our inventory dropped below a /8. ARIN’s current inventory will continue to be distributed using the same policies that we have been following.  The major change implemented in Phase Four is the method in which IPv4 requests are reviewed and processed.

4.  ARIN treats small ISPs differently than they treat large ISPs

Absolutely untrue.   ARIN strictly adheres to its mandate to treat all requestors in a fair and equitable manner in accordance with the community developed policies documented in the Number Resource Policy Manual.  We work hard to ensure that all organizations can obtain the amount of IP address space that they can justify under the current set of policies.

5. IPv4 shortage isn’t a good enough reason to prepare for IPv6

IPv4 depletion is THE reason to make sure you have a plan to deploy IPv6.  Solutions that people have suggested to extend the life of IPv4 (think NAT, reclaiming unused IPv4 space, a transfer market, etc.) are only temporary solutions that will not suffice for the long term. IPv4 address space is simply not large enough in its entirety to meet the addressing needs of the global Internet. IPv6 implementation is the only viable solution to the dwindling pool of available IPv4 space.

Post written by:

Leslie Nobile
Senior Director, Trust and Public Policy

Recent blogs categorized under: IPv4

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