Net giants Google, Facebook, Akamai and Yahoo have committed to taking part in the "test flight" of IPv6.

Net firms are being encouraged to switch to IPv6 as addresses in the old scheme will run out by November 2011.

"The good news is that internet users don't need to do anything special to prepare for World IPv6 Day," said Lorenzo Colitti, a network engineer at Google in a blog post.

"Our current measurements suggest that the vast majority (99.95%) of users will be unaffected. However, in rare cases, users may experience connectivity problems, often due to misconfigured or misbehaving home network devices."