Operators activated the protocol just after midnight, paving the way for the creation of trillions of new IP addresses to support the growing number of connected tablets and smartphones.
"World IPv6 Launch is a permanent step forward to ensure the internet can connect all the people in the world, for many years to come," said Leslie Daigle, Chief Internet Technology Officer for the Internet Society.
The new system will replace IPv4, which has been around since the early days of the internet. Just over 4 billion unique IP addresses were available under the old standard.
With sharp increases in internet traffic across the world, there were concerns that more and more devices would have to share IP addresses, resulting in slower connection speeds. However, the average web user is unlikely to notice any difference under IPv6.
Google, Facebook and other internet giants have already taken the system on board to encourage widespread adoption.
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