Running Out of Numbers? The Impending Scarcity of IPv4 Addresses and What To Do About It
June 6, 2008
The Internet's current numbering system is nearing exhaustion: The Internet's primary communications protocol, "IP" (more precisely, IPv4) allows only a finite set of computer numbers ("IP addresses"), and central authorities will soon exhaust the supply.
An alternative IP standard, IPv6, would dramatically increase Internet address capacity. But network incentives impede transition to v6. For example, a device with only a v6 address cannot directly retrieve most web sites because most web sites have only v4 addresses. Consider the undesirability of owning the world's first fax machine (no one to communicate with); to date, v6 has suffered a similar problem, with the additional challenge that existing IPv4 systems boast widespread usage (making an upgrade to v6 appear particularly unnecessary). Furthermore, v4-v6 translation systems are limited at best -- allowing v6-only computers to receive some kinds of v4 content, but often failing to support proprietary or nonstandard systems such as VoIP, videoconferencing, multiplayer video games, and custom software.
With these substantial disincentives and limitations hindering v6 transition, v6 deployment has been slow. It seems continued use of IPv4 will remain necessary for the foreseeable future -- even after central authorities have no more v4 addresses to give out. Today I'm posting an initial analysis of market mechanisms to reallocate existing v4 addresses and facilitate v4's continued use. In particular, I consider the possible effects of paid transfers of v4 addresses. I emphasize rules to ameliorate the worst effects of v4 scarcity, while preserving the core principles of existing regulation and avoiding major negative externalities.
Running Out of Numbers? The Impending Scarcity of IP Addresses and What To Do About It
Note: This draft is a work in progress, pending submission to an academic conference later this month. I anticipate further revisions in the coming weeks. I welcome comments and feedback.
Disclosure: I provide advice to ARIN’s counsel on matters pertaining to v6 transition, v4 exhaustion, and possible revisions to ARIN's v4 transfer policy. But this paper expresses only my own views – not the views of ARIN, its Board, or its staff. I write on my own behalf, not for ARIN, nor at ARIN's instruction or request.