A notable point in the history of the Internet was reached on February 3 with the allocation of the last remaining IPv4 (Internet Protocol version 4) Internet addresses from a central pool. IPv4 has served as the Internet’s main communications protocol for more than 20 years, but future expansion of the Internet is now dependent on the successful global deployment of the next-generation Internet protocol, IPv6.
The announcement was made jointly by the Internet Corporation for Assigned Names and Numbers (ICANN), the Number Resources Organization (NRO), the Internet Architecture Board (IAB) and the Internet Society — the four international non-profit groups that collaboratively work to coordinate the world’s Internet addressing system and its technical standards.
The final allocation of Internet addresses was administered by the Internet Assigned Numbers Authority (IANA), which is a function of ICANN.
“This is a major turning point in the ongoing development of the Internet,” said Rod Beckstrom, ICANN’s President and Chief Executive Officer. “No one was caught off guard by this. The Internet technical community has been planning for IPv4 depletion for some time. But it means the adoption of IPv6 is now of paramount importance, since it will allow the Internet to continue its amazing growth and foster the global innovation we’ve all come to expect.”
The final two “blocks” of IPv4 addresses, about 33 million of them, were allocated in February to the Regional Internet Registry (RIR) for the Asia Pacific region. When that happened, it meant the pool of IPv4 addresses had been depleted to a point where a global policy was triggered to immediately allocate the remaining small pool of addresses equally among the five global Regional Internet Registries. The RIRs are independent, not-for-profit organizations that provide technical coordination for the infrastructure of the Internet.
The allocation of the final IPv4 addresses is analogous to the last crates of a product leaving a manufacturing warehouse and going to the regional stores or distributions centers, where they can still be distributed to the public. Once they are gone, the supply is exhausted. In this case, the RIRs will distribute the last IPv4 addresses to Internet service providers, universities, governments, telecommunications companies and other enterprises.
“It’s only a matter of time before the RIRs and Internet service providers (ISPs) must start denying requests for IPv4 address space,” said Raúl Echeberría, Chairman of the Number Resource Organization, the umbrella organization of the five RIRs. “Deploying IPv6 is now a requirement, not an option.”
IPv6 will open up a pool of Internet addresses that is a billion-trillion times larger than the total pool of IPv4 addresses (about 4.3 billion), which means the number of IPv6 addresses is virtually inexhaustible for the foreseeable future. In addition to almost infinite address space, IPv6 offers built-in security and enhanced support for streaming media and peer-to-peer applications. Although it has been available for a decade, IPv6 has been slow to catch on while IPv4 addresses were still available.
For most organizations, the delay is due to the lack of a clear path to transition. IPv4 and IPv6 are different protocols and are not directly compatible, so programs and systems designed to one standard cannot communicate with those designed to the other.
This is not considered a significant barrier, however. Some of the strategies for making the transition include running dual-stack IPv4 and IPv6 hosts and networks, performing IPv6-to-IPv4 translation, tunneling, and using proxy servers to facilitate a migration to the new address space as software allows.
The effort and expense of changing to IPv6 will fall mostly on Internet service providers, Web sites and network operators that have to make sure systems can handle the new online addresses and properly route traffic. Consumers, for the most part, shouldn’t notice the switch because complex IP numbers would still appear to them as words and domains.
While there are bound to be instances of service disruptions and other headaches, Google engineer Lorenzo Colitti, who is leading the Internet giant’s transition to the new standard, dismissed the notion of an “IPocalypse” that would dramatically affect Internet performance.
“It is important that users don’t worry,” said Colitti. “But it is important that we as an industry work together.”
