IPv4 Really Tired, But Not Totally Exhausted

The number of IPv4 Internet addresses continues to dwindle, and they aren't making any more. That's now prompting behind-the-scenes changes in how Internet addresses are distributed, and focusing attention on the effort to prepare networks and infrastructure for the coming of the next-generation IPv6 protocol.

In a significant milestone in the transition from IPv4 to IPv6, earlier this week the Internet Assigned Numbers Authority (IANA) distributed the final unreserved IPv4 address blocks to APNIC, one of five Regional Internet Registries (RIRs). This triggers a process in which the final five blocks of IPv4 addresses are distributed to the RIRs to provide for fair distribution of the remaining addresses. This process is likely to be announced tomorrow.

IPv4 Entering Final Months

The registries will have IPv4 addresses available for a short while. AP{NIC, fort examples, ex[ects its supply to last another three to six months. There will also be efforts to reclaim and reassign IPv4 addresses that remain unused.

While this week's news isn't yet the "IPv4-mageddon," it makes the coming depletion of IPv4 a lot more real, and may jump-start the IPv6 readiness process for companies that have been dragging their feet.

IPv6 will dramatically expand the number of addresses available for web sites, as well as millions of mobile devices with Internet access. A few months back we had a Q-and-A with John Curran, president and CEO of the American Registry for Internet Numbers (ARIN) about the process.

A Slow, Rolling Transition

"IPv6 adoption will be a slow, rolling transition as IPv4 space fully depletes," Curran told DCK. "The global free pool, from which all five Regional Internet Registries get address space, will deplete first. Then, the RIRs’ supplies will deplete as they allocate their remaining address space to network operators. Finally, the network operators’ own address space will be fully depleted."

At some point there will be no IPv4 addresses available from registries like ARIN, but other parties will continue to possess unused IPv4 addresses, which may suddenly have value. Will there be a market for these addresses?

"ARIN has a 'Transfers to Specified Recipients' policy in place that allows an organization to transfer its Internet number resources to another organization in the ARIN region, provided the recipient organization receives them under ARIN contract and can justify its need for the resources," said Curran. "ARIN operates a Specified Transfer Listing Service to facilitate these transactions, though organizations are not required to use the listing service to use the transfer policy. We believe that these are sufficient tools for those organizations that might need some additional time in their migration to IPv6."

One of the leading players in IPv6 has been Hurricane Electric, which this week warned that there are costs in being a laggard in making your network and equipment IPv6-ready.

"In order to avoid costly capital expenditures down the road and possible failure on their business continuity plans, companies must make the migration to IPv6 sooner rather than later," said Martin Levy, Hurricane Electric’s Director of IPv6 Strategy. "Companies that fail to migrate to IPv6 will face a number of painful options, including buying expensive equipment to cobble together an address-sharing scheme or going out to the marketplace to acquire IP address space at a potentially exorbitant price."