With World IPv6 Day approaching on June 8, the next-generation Internet protocol could finally be trickling into use as carriers gain the confidence to use it in its native mode, a new traffic analysis by Arbor Networks has suggested.
The company analyzed inter-domain traffic through the 110 major Internet carriers hooked into its Atlas packet observation system, and found that between August 2010 and February this year, "tunneled" IPv6 volumes decreased sharply from 0.04 percent to 0.01 percent of all Internet traffic. Over the same period, by contrast, IPv4 surged by between 40 and 60 percent.
Although it sounds paradoxical, Arbor takes this to be a positive sign that carriers are finally abandoning the hugely inefficient but sometimes necessary practice of burying or tunneling IPv6 packets inside IPv4 ones by enabling IPv6 in its native mode.
To test this hypothesis, Arbor then analyzed traffic from a subset of six carriers from the original 110 and found that over the same period native IPv6 had indeed increased in volume from 0.1 percent of all Internet traffic to around 0.2 percent.
The choice of six carriers wasn't an arbitrary number -- these were the only ones out of the 110 Atlas members that had routers capable of exporting IPv6 native-use data for Arbor to capture, which tells a story of its own.
"One of the biggest challenges of IPv6 is simply measuring it," admitted Arbor chief scientist Craig Labovitz. The lack of infrastructure made it impossible to know with any certainty what was happening and how fast, he said.
Nevertheless, although IPv6 remained small in absolute terms he believed the growth in native IPv6 use over a relatively short space of time was significant.
Less positive, perhaps, is what people appear to be using IPv6 for. Using Arbor's best-guess application analysis, the dominant use appears to be for P2P, particularly uTorrent, a file-sharing system whose users have adopted IPv6 as a way of hiding from ISPs.
World IPv6 Day, a 24-hour test for IPv6 backed by Google, Facebook, Yahoo and Akamai among others, will be a key moment, said Labovitz. If the industry fails to take up IPv6 quickly enough there is a danger that as the remaining IPv4 address space dwindles, the Internet might undergo an unintended economic shock.
"There is a danger of things becoming much more expensive and failing to work as well," said Labovitz. "We are going down the rabbit hole as to what might happen next. There is a danger of events overtaking us."
"We are hopeful that it [World IPv6 Day] will give carriers the confidence to enable IPv6 by default," he said.
Labovitz promised to return with new figures after June 8 and was confident that IPv6's long, slow haul up the traffic table will have begun in earnest after more than a decade of ignominious false dawns.