Search engine giant Google has publicly backed IPv6, the long-anticipated upgrade to the Internet's main communications protocol, after its engineers said it was not expensive, and required only a small team of developers to enable all of the company's applications to support it.

"We can provide all Google services over IPv6," said Google network engineer Lorenzo Colitti during a panel discussion held Tuesday at a meeting of the Internet Engineering Task Force (IETF).

Colitti said a "small, core team" spent 18 months enabling IPv6, from the initial network architecture and software engineering work, through a pilot phase, until Google over IPv6 was made publicly available. Google engineers worked on the IPv6 effort as a 20 percent project - meaning it was in addition to their regular work - from July 2007 until January 2009.

Building a pilot IPv6 network "was not expensive," said Colitti, who recommended rolling out IPv6 in stages. "There's nothing inherently unreliable about IPv6."

Google is already reaping the benefits of IPv6. "It's refreshingly simple" to look at a network with globally addressable devices, Colitti said.

Google's comments at the IETF meeting come days after the search engine giant held a conference in Mountain View, California, for IPv6 implementers.

Also in March, Google published a manifesto on its public policy blog explaining why IPv6 matters.

Google's experience with IPv6 is significant because only a handful of leading-edge US companies have embraced the next-generation Internet protocol.

The IETF created IPv6 in 1995 as a replacement to the existing version of the Internet Protocol, known as IPv4.

IPv6 is needed because the Internet is running out of IPv4 addresses. IPv4 uses 32-bit addresses and can support approximately 4.3 billion individually addressed devices on the Internet. IPv6, on the other hand, uses 128-bit addresses and can support so many devices that only a mathematical expression - 2 to the 128th power - can quantify its size.

Experts predict IPv4 addresses will be gone by 2012. At that point, all ISPs, government agencies and corporations will need to support IPv6 on their backbone networks.

Besides Google, other early adopters of IPv6 include the U.S. federal government and Bechtel.

Colitti said Google has accepted that IPv6 is a requirement for any company that wants to see the Internet continue to operate and to support new applications and users.