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ARIN Enters Phase 4 of IPv4 Exhaustion

ARIN is now down to their final /8 equivalent block of IPv4 addresses.

After IANA allocated the final IPv4 addresses to the five Regional Internet Registries (RIRs) on February 3, 2011, the RIRs have been running out of IPv4 addresses over the past three years. APNIC ran out on April 15, 2011; RIPE NCC ran out on September 14, 2012; and now ARIN has reached their final /8 address amount on April 23, 2014. LACNIC will run out sometime this year, and AFRINIC may not run out for a couple of years. Now, organizations in Canada, the U.S., and some nearby islands will encounter increased obstacles to receive any more IPv4 address allocations. Don’t be too alarmed, you have options.

The Internet community has been planning for the eventual exhaustion of IPv4 addresses since the early 1990s. The IETF Address Lifetime Expectations (ALE) Working Group analyzed the use of IPv4 address blocks and helped lead to the deployment of Classless Interdomain Routing (CIDR) which helped extend the longevity of the Internet. The IETF then started to work on IPv6 in the early 1990s with the realization that IPv4 would not be able to scale indefinitely. The IETF knew it would take a long time to design, create, and implement a new Internet protocol. However, it was clear that the Internet needed a new protocol that used much larger address fields. Now, IPv6 is implemented in virtually all modern operating systems, available in all network equipment, and almost all ISPs offer IPv6 Internet connectivity.

The RIRs have been running out of IPv4 addresses for years, so this should not be a surprise to anyone. Each RIR has their own “soft-landing” approach to gradually exhausting their supply of addresses. Each RIR has had a different rate of consumption, but they have all experienced a growing customer base as the growth of the Internet has required more addresses.

After today’s announcement by ARIN, they have now entered Phase 4 of their IPv4 exhaustion plan. Their Number Resource Policy Manual (NRPM) defines the process that organizations can request IPv4 addresses. You can check ARIN's inventory at this site.  ARIN will continue to allocate addresses to requesters, but with increased review.  ARIN also has a /10 that is being used to help facilitate transition to IPv6.  However, over time, ARIN will continue to draw down their IPv4 address supply.

This may be concerning for many organizations that intend to continue using IPv4 for decades to come. There are probably no organizations in the ARIN territories that are actively planning to stop using IPv4 at some point in the future. Their businesses will continue to grow and their dependence on Internet connectivity to operate their businesses will increase. The growth of Internet innovation will be hampered by this shortage of IPv4 addresses. Organizations that are desperate for addresses can purchase them through the address transfer marketplace. ARIN permits address transfers to take place, but you must follow their rules as part of the address transfer process. Over time, the price of an IPv4 address will increase from $15 to $30 today to well over $100 in the distant future.

Enterprise organizations should be actively planning to adopt IPv6. This is the only protocol that is available that is feasible for use on the Internet and it is in use today. Your organization should be making a request for IPv6 address space today and starting to plan your IPv6 deployment at your Internet edge. Over the coming years, your organization should be planning to migrate IPv6 slowly inward into your internal networks.

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