Press Release

Press Release

01 July 2015

Kim Kaull

ARIN Activates Waiting List for IPV4 Addresses

- Registry Stresses Need for IPv6 Adoption as IPv4 Addresses Run Out -

Chantilly, VA - 01 July 2015 - Noting an important development for the Internet community, the American Registry for Internet Numbers (ARIN), a nonprofit association that manages the distribution of Internet number resources within its region, announced today that it has activated its Unmet Request Policy with the approval of an address request that was larger than the available inventory in the regional IPv4 free pool.

Activation of this policy is another sign of the impending depletion of unassigned IPv4 resources in the ARIN region, reminding businesses of the need to deploy the next generation Internet Protocol, IPv6, and usher in the next stage of the Internet's evolution. Qualifying organizations now have the choice of accepting the next largest available block of IPv4 addresses or being placed on the Waiting List for Unmet IPv4 Requests.

IPv4 is based on a 32-bit system and provides approximately 4.3 billion possible Internet addresses. The new standard Internet addressing system, IPv6, employs a 128-bit identifier, allowing for 3.4×1038 IP addresses; that may also be expressed as 340 trillion trillion trillion (340 undecillion) IP addresses, which is more than a trillion IP addresses for every known star in the universe.

"IPv4 was introduced more than three decades ago, and even the architects of the Internet could not have predicted the amazing success and universal adoption of the Internet and World Wide Web," said ARIN president and CEO John Curran. "Since its introduction, IPv4 has served as the foundation for the global Internet as we know it today. With the coming depletion of IPv4 address space, it is time for Internet service providers to move to IPv6 to enable the Internet's continued growth. Businesses should be aware that this transition is already well underway for many service providers in the region and make sure that their public-facing websites are reachable via IPv6 for the best performance." 

While ARIN does still have very limited amounts of IPv4 address space available in smaller block sizes, the registry encourages customers to monitor the IPv4 Inventory Counter on the ARIN homepage and the breakdown of the remaining IPv4 inventory found on its IPv4 Depletion page. Organizations that need any larger amounts of IPv4 address space can make use of the IPv4 transfer market for their immediate needs, and should accelerate their IPv6 transition plans. Information on IPv6 can be found at

ARIN is hosting a recurring blog series on IPv4 depletion status on the TeamARIN website to keep the community informed about the status of the ARIN IPv4 free pool. ARIN also encourages its customers with questions on IPv4 availability to contact or its Help Desk +1.703.227.0660.


About the American Registry for Internet Numbers (ARIN)

ARIN is the nonprofit corporation that manages the distribution of Internet number resources – IPv4, IPv6, and Autonomous System numbers – in its service region, which includes Canada, many Caribbean and North Atlantic islands, and the United States. More information on IPv6 adoption is available at and