Internet giants celebrated IPv6 Day by moving their platforms to the new internet protocol.

Leslie Daigle, chief Internet technology officer for the Internet Society, said World IPv6 Day was designed to motivate service providers, website operators, hardware makers and software suppliers to test-drive IPv6 and to identify any remaining technical issues that need to be resolved with this emerging technology.

"It was perceived to be quite a successful day," Daigle said. "It was an amazing display of cross-industry participation. ... It's an important step in the Internet's progress. We are running out of IPv4 addresses, and IPv6 is definitely the way to move forward to make sure the Internet is a platform for innovation."

One day after completing a successful 24-hour trial of IPv6, Facebook, Google and Yahoo said at a joint press conference that they would begin permanently supporting this upgrade to the Internet's main communications protocol on some of their key websites.

IPv6 features an expanded addressing scheme, so it can handle vastly more devices connected directly to the Internet than its predecessor called IPv4. However, IPv6 is not backward compatible with IPv4, which means website operators have to upgrade their network equipment and software to support IPv6 traffic.