The IANA IPv4 Free Pool has Depleted

The IANA IPv4 Free Pool has Depleted

The global free pool of IPv4 depleted on this day, 3 February 2011. This historic event was reported by the Internet Assigned Numbers Authority, which allocated two IPv4 address blocks to APNIC and then its final five /8 blocks to each of the five Regional Internet Registries per global policy.

IPv4 exceeded all of the expectations of its designers. First issued in 1981, it was only intended to interconnect a few research organizations and government agencies, but it rose to prominence in support of a global commercial Internet. IPv4 paved the way for the Internet to become a highly robust, dynamic, and geographically diverse medium that has changed the way the people of the world work and learn.

During the 1980s and 1990s, an explosion of Internet-enabled devices and services led to a worldwide need for unique IP addresses to connect them, and it was the success of the Internet that will lead to IPv4’s ultimate exhaustion. Its four billion IP addresses, despite careful stewardship and innovative engineering practices, are not enough to meet the ever growing needs the global internet and all of the devices that connect with it.

ARIN will still be allocating from its own pool of IPv4 address space, as long as we are able, but there will be a pressing need for organizations to begin to actively implement IPv6. With over 340 undecillion IP addresses, IPv6 is the future of the Internet.

ARIN President and CEO, John Curran emphasized “We still have that last /8 from the free pool, plus our existing inventory. We will continue to allocate IPv4 address space for as long as possible. At the same time, though, we look forward to the Internet moving to IPv6.“

Full text of the related NRO announcement is available at and ARIN’s announcement is available at

Post written by:

Jason Byrne
Senior Customer Success Analyst

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