will involve major Web companies enabling Internet Protocol version six (IPv6) on their main websites for 24 hours in order to run a "global-scale test flight" of the replacement internet protocol to IPv4.

During the experiment, service providers will coordinate to disable IPv6 connections to any users experiencing difficulties.

Global internet registry IANA is currently estimated to allocate its last lot of IPv4 addresses to regional registries sometime in February this year - well before the date set for global cooperation on the issue.

The local registry for Australia, APNIC, is also expected to run out of addresses this year, with chief scientist, Geoff Huston, telling it may be exhausted by July or August.