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ARIN: IPv4 Free Pool Runs Dry

If you don’t have an IPv6 strategy that’s already in place or at least well downstream, you’re in big trouble.

The American Registry for Internet Numbers (ARIN) announced Thursday that the free pool for IPv4 addresses has reached “zero” following the issuance of its final addresses.

ARIN, president and CEO John Curran said in a blog post, will “continue to process and approve requests for IPv4 address blocks, and approved requests can be filled out via the Wait List for Unmet IPv4 Requests or via the IPv4 Transfer Market.

“Effective today, because exhaustion of the ARIN IPv4 free pool has occurred for the first time, there is no longer a restriction on how often organizations may request transfers to specified recipients,” Curran noted. “If we are able to fully satisfy all of the requests on the waiting list, any remaining IPv4 addresses would be placed into the ARIN free pool of IPv4 addresses to satisfy future requests.”

Many U.S. network operators have been preparing for this day by transitioning to IPv6 and its virtually unlimited supply of addresses. ARIN has been issuing warnings about IPv4 depletion for years. 

According to Akamai’s just-released Q2 2015 State of the Internet report, cable and wireless/mobile providers drove the largest volumes of IPv6 requests – Verizon Wireless (71%); T-Mobile (44%), Comcast (37%), AT&T (35%) and Time Warner Cable (18%). On a global basis, Belgium’s IPv6 request volume to Akamai led with 38%, followed by Switzerland (23%), the U.S. (19%), Peru and Germany (17%), and Luxembourg (14%).

For its part, Comcast announced in July 2014 that its broadband network has been fully deployed to support IPv6 dual stack connectivity, a milestone that factored in as the pool of IPv4 addresses inched toward depletion.

John Brzozowski, fellow and chief IPv6 architect at Comcast Cable, blogged today that the ARIN announcement is “not the beginning of the end” but “just the end of the beginning.”

“The news comes as no surprise, but it will force companies and organizations worldwide to accelerate their transition to the more robust, secure and modern version of the Internet protocol, IPv6,” he wrote.

Regarding Comcast’s IPv6-facing work, he noted that the MSO now has “tens of millions” of cable modems being managed using IPv6-only lltoday, and that less than 5% of cable modems on Comcast’s network now rely on IPv4. Cable's widely deployed DOCSIS 3.0 platform supports IPv6. 

Additionally, more than 70% of Comcast broadband subs (residential and commercial0 are actively provisioned with IPv6 support today, and that “well over 15 percent of Comcast’s Internet traffic is over IPv6.”

All of Comcast’s products and services are geared for or will soon be geared for IPv6. For example, X1, Comcast’s next-gen, IP-capable video platform, is migrating to IPv6, he said.