IPv6 Transition:Georgia Tech Report Predicts Indefinitely 'Mixed World'

Posted February 20, 2019

The original system for doling out addresses on the internet, long believed destined for replacement amid an explosion in demand, is now likely to survive indefinitely alongside a newer, more capable standard, according to a major new study published Feb 20, 2019, by the Georgia Institute of Technology’s Internet Governance Project.

The original protocol, called IPv4, is almost 40 years old, and its 32-bit address space is too small for the global internet. A newer protocol, IPv6, has a much larger 128-bit address space, but is not backward compatible with the existing internet. For 20 years, the technical community has been trying to migrate the entire internet to the new standard, with only limited success.

While many promoters of IPv6 believe a complete transition to the new protocol is inevitable and necessary, the IGP report finds that smaller and more budget-constrained networks can let bigger and richer networks convert to the new standard and still have access to the same Internet. Instead of converging on IPv6, a variety of conversion technologies and more efficient use of IPv4 addresses through use of address-remapping techniques will support a “mixed world” of the two standards for the foreseeable future, IGP researchers found.

“The co-existence of these dual standards may actually facilitate continued internet growth, but it will make global networking more complicated. We need to stop assuming that IPv6 will eventually take over and begin to think about the implications of a mixed world,” said Brenden Kuerbis, a postdoctoral fellow at the IGP who co-authored the study with Milton Mueller, director of the IGP and a professor in the School of Public Policy. The school is a unit of the Ivan Allen College of Liberal Arts.

The study, “The Hidden Standards War: Economic Factors Affecting IPv6 Deployment,” was supported in part by the Internet Corporation for Assigned Names and Numbers (ICANN)’s Office of the Chief Technology Officer.

The research offers a clear-eyed, economically-grounded study of IPv6’s progress and prospects. By examining the associated network effects, developing the economic parameters for transition, and modeling the underlying economic forces which impact network operator decisions, the study paints a more complex, nuanced picture of the future of the two protocols and reaches several important conclusions.

The good news for IPv6 is:

  • IPv6 will not become an orphan. Major content providers and fast-growing mobile internet services are deploying IPv6 and gradually diverting traffic away from the old internet to native IPv6 networks. It appears as if IPv6 will dominate some parts of the newer, larger-scale parts of the internet.
  • For network operators that need to grow, particularly mobile networks where the software and hardware ecosystem is mostly converted, IPv6 deployment can make economic sense. It mitigates a major constraint on growth and reduces the operational complexities and costs of large-scale Network Address Translation.

But there is also bad news for IPv6:

  • The incentives of large, fast-growing network operators are not the same as those of many other networks that make up the internet. Many enterprise networks do not need to grow as much and may still be lodged in a slower-moving software and hardware ecosystem tied to IPv4.
  • Diffusion is still in early days. Of the 215 economies measured, only 26 (12%) had steadily increasing levels of IPv6 capability over the three year study period. Another 18 countries (8%) had measurable levels of IPv6 deployment but exhibited plateaus in adoption, with IPv6 capability stalled for several years at levels anywhere between 8% (Austria) and 59% (Belgium). This group included numerous mature European economies as well as Canada and Australia. A large majority of economies (169, or 79%) had no appreciable IPv6 deployment. Countries in this group were located in all regions, and included small economies, such as Mozambique, and large ones, such as China.
  • Networks that deploy IPv6 must maintain backward compatibility with those that do not. This imposes a cost penalty on IPv6 users and eliminates some network effects that would degrade or cut off networks that do not convert.
  • Even if they have deployed IPv6, growing networks must continue to acquire scarce, increasingly expensive IPv4 addresses to interconnect with the rest of the internet. Deploying IPv6 does not immediately end the problem of IPv4 address exhaustion.

The study examined the impact of IPv4 address markets and address scarcity on the transition. The authors point out that cloud service providers, who need to serve networks using both protocols, are the buyers of the largest amount of IPv4 numbers.

The IGP is comprised of professors, postdoctoral researchers, and students hosted at the School of Public Policy at the Georgia Institute of Technology, one of the world’s leading engineering universities. IGP conducts scholarly research and produces timely policy analyses and public commentary on current events in internet governance. IGP and its partners also educate professionals and young people about internet governance around the world.