Internet policymakers officially handed out the last five blocks of IPv4 address space to each of the Regional Internet Registries (RIRs) at a ceremony held in Miami Thursday morning.
BACKGROUND: IPv4 exhaustion predicted
The ceremony marked the depletion of the free pool of addresses for IPv4, the main communications protocol that underpins the Internet. The ceremony's goal was not only to celebrate this historic milestone in the Internet's 40-year history, but also to demonstrate that this precious resource of IPv4 addresses was doled out in an equitable fashion around the globe.
Policymakers -- including the Internet Assigned Numbers Authority (IANA) and the Internet Corporation for Assigned Names and Numbers (ICANN) -- used the ceremony to underscore the need for network operators and content providers to migrate to IPv6, the long-anticipated upgrade to IPv4.
"This is one of the most important days of the Internet," said Rob Beckstrom, ICANN's President and CEO. "A pool of more than 4 billion Internet addresses has been emptied ... This marks the opportunity to shift to a version of IP that is so large it is difficult to even imagine ... and that can carry us into the future.''
IPv4 uses 32-bit addresses and can support 4.3 billion devices connected directly to the Internet. IPv6, on the other hand, uses 128-bit addresses and supports a virtually unlimited number of devices -- 2 to the 128th power.
PANIC TIME QUIZ: How prepared are you for IPv6?
Each of the RIRs was given what is called a /8 block of IPv4 addresses, which is around 16.7 million addresses. Experts say it will take anywhere from three to seven months for the registries to distribute the remaining IPv4 addresses to carriers.
Once the registries hand out all of the IPv4 addresses, network operators must either deploy complex, expensive network address translation (NAT) technologies to share IPv4 addresses among multiple users, or adopt IPv6.
COMPARISON: IPv6 vs. Carrier-Grade NAT
The Internet engineering community used the Miami event as an opportunity to encourage network operators and content providers to quickly adopt IPv6.
"Today begins the final chapter of IPv4," said Lynn St. Amour, president and CEO of the Internet Society. "The sooner we all move to adopt IPv6, the better and brighter our future will be ... The fundamental key to the Internet's success is the unification of networks through globally addressing. That is why so many have stepped up to deploy IPv6."
Olaf Kolkman, chairman of the Internet Architecture Board, warned that network operators and content providers need to adopt IPv6 because the available technical workarounds will become increasingly difficult to support.
"The next 2 or 3 billion Internet users will use IPv6 only," he warned, but he added that coexistence between the two protocols will continue for decades. "As long as there will be people that have legacy equipment with IPv4, there will need to be a reason to communicate with IPv4."