IPv6 Test Flight Has Risks – But Huge Benefits

On 8 June 2011, the Internet will hold its breath, as the IPv6 test flight takes off. But what is under test is not the new Internet protocol, but the sites which have decided to publicly implement it.

For 24 hours, in universal time (so it starts and finishes at midnight in the UK) the world’s largest sites, including Facebook, Google and Yahoo, have all promised to switch on routing using the new Internet protocol, IPv6, in a test run by the Internet Society (ISOC). And, if the test works, there will be no visible result at all.

Two possible futures: IPv6 or death by NAT

The current protocol, IPv4, will still carry on working, says Leslie Daigle, the Internet Society’s chief Internet technology officer. But switching on IPv6 is a matter of urgency, because sometime this year the IPv4 addresses will run out,  and the world will then have two possible futures.

“Either we have more people, on IPv6, or they have IPv4 and have to use a heavily NATed network, and providers like Google are aware what their service looks like when viewed through a heavily NATed network,” she said. “The future that does not exist is continuing to use the current IPv4 network as it is.”

Network address translation (NAT) is the technique that has enabled IPv4 to serve the world for decades – when it was predicted that its address space would fill up in the mid 1990s. Although it makes sure that systems can reach each other, the layers of translation limit the performance of the Internet, and native IPv6 addresses should open things up.

IPv6 will allow a vast number of individually addressable devices, making way for the mobile revolution and an explosion of connected devices such as sensors, all of which could be be made to work on IPv4, just… but will work much better on IPv6.

“We want to make sure we continue to have an open Internet with global addresses, that continues to allow innovation from everywhere,” said Daigle.

IPv4 – a test of polite behaviour

IPv4 allows four billion addresses, which seemed plenty when the Internet first emerged, but those addresses are running out fast now, with only five percent remaining in December.

“IPv4 addresses will run out in the coming months, with various predictions for exactly when,” said Daigle. “In a few weeks we will have allocated all of them to the world’s registries, and individual regions will then allocate them according to their policies, and will run out at different times.”

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