YouTube confirmed that it now supports IPv6, the long-anticipated upgrade to the Internet's main communications protocol, in a blog post.

"We're proud to make YouTube available over IPv6 and to begin streaming videos from a select number of sites worldwide to our Google over IPv6 partners," wrote Lorenzo Colitti, a Google network engineer. "With YouTube on board, we now have a significant amount of content delivered on IPv6 and a real audience/traffic for it."

Earlier in the week, ISPs guessed that YouTube had begun production-level support for IPv6 because they saw a huge surge of IPv6 traffic leaving YouTube's data centres worldwide.

In his blog post, Colitti said support of IPv6 was necessary to allow more people and devices to attach directly to the Internet.

IPv6 is "a win for openness and new applications because any device can connect to any other device on the Internet," Colitti wrote. "It's even a win for security, because it's harder for hackers to find your computer and attack it."

The Internet is running out of addresses using the current version of the Internet Protocol, known as IPv4. IPv4 uses 32-bit addresses and can support approximately 4.3 billion devices.

More than 90% of IPv4 addresses have already been assigned. The conventional wisdom of the Internet industry is that the rest of the IPv4 addresses will be allocated in 2012.

That's why websites like YouTube are upgrading to IPv6. With 128-bit addresses, IPv6 can support so many devices that only a mathematical expression, 2 to the 128th power, can quantify its size.

In order to use YouTube's new IPv6 service, users will need an IPv6 connection from their ISPs.

Google is a leader in IPv6 deployment, having already IPv6-enabled its Search, Alerts, Docs, Finance, Gmail, Health, iGoogle, News, Reader, Picasa, Maps, Wave, Chrome and Android products.

Other popular websites – including Facebook, Yahoo and eBay – are committed to deploying IPv6 within the next 18 months.