The Internet's biggest players -- including Facebook, Google, Yahoo and Bing -- are turning on IPv6 today as part of the World IPv6 Launch Day challenge coordinated by the Internet Society. But which websites are not ready to support the next-gen Internet Protocol?
Well, Twitter, for one. When asked about the real-time information sharing site's progress on IPv6 and why the company isn't participating in World IPv6 Launch Day, Twitter spokesman Robert Weeks said: "Twitter is looking to enable IPv6 as soon as we can." In the meantime, there is no IPv6-based access for Twitter, which has more than 100 million active users.
Other high-profile sites that aren't among the 3,000 participants in World IPv6 Launch Day are business-oriented social networking site LinkedIn, e-commerce giants Amazon and eBay, and classified advertising service Craigslist. Neither Tumblr nor Pinterest -- two popular image-sharing websites --- is participating in World IPv6 Launch Day. Nor is PayPal.
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Indeed, of Alexa's Top 50 most popular websites in the United States, only 12 -- or 24% -- are listed as participants in World IPv6 Launch Day.
That means 76% of the 50 most popular U.S. websites aren't ready for IPv6 traffic.
"As far as the laggards are concerned, if they are not actively working on IPv6 then the only progress they are making is to make themselves irrelevant," said Owen DeLong, IPv6 evangelist and director of professional services at Hurricane Electric, a leading IPv6 service provider.
"I understand that there are naysayers out there, but as of the sixth of June, IPv6 will be deployed," said Leslie Daigle, chief Internet technology officer at the Internet Society. "With 50 participating network access providers enabling IPv6 for 1% of their subscribers on June 6, that will be a big enough percentage of Internet traffic to catch the attention of business decision-makers."
World IPv6 Launch Day is a voluntary event designed to bring momentum to IPv6, the long-anticipated upgrade to the Internet's main communications protocol, which is called IPv4. IPv6 is needed because the Internet is running out of addresses with IPv4. Asia ran out of unassigned IPv4 addresses last year, Europe is expected to deplete its supply this summer, and North America's will expire next year.
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IPv4 uses 32-bit addresses and can support 4.3 billion devices connected directly to the Internet. IPv6 uses 128-bit addresses and can connect up a virtually unlimited number of devices: 2 to the 128th power. Deployment of IPv6 has been hampered by the fact that it is not backward compatible with IPv4. So network operators must either deploy both protocols in what's called dual-stack mode or translate between them, which adds latency and cost.
Internet policymakers have been trying to drum up support for IPv6 with events like World IPv6 Launch Day, which has been successful in raising the visibility of IPv6. But there's no question that encouraging U.S. companies to deploy IPv6 remains an uphill battle.
"With World IPv6 Launch Day on June 6, organizations have got to make sure they have IPv6 plans or they are not selling complete Internet services," said John Curran, president and CEO of the American Registry for Internet Numbers, which provides IPv4 and IPv6 addresses to U.S. network operators. "On June 6, ISPs are turning it on and leaving it on permanently. This is the day that the Internet is now dual-stack, IPv4 and IPv6."
U.S. corporations that aren't participating in World IPv6 Launch Day include publishers such as The Huffington Post and The New York Times and broadcasters such as CNN, ESPN and Fox News. Among entertainment companies, neither Hulu nor Disney is participating. Bank of America, Wells Fargo and Chase Bank aren't signed up, and neither is Walmart or the Weather Channel.
Even the leading online porn sites -- LiveJasmin and PornHub -- appear to be IPv6-free for now.
"There are definitely people living in denial about the inevitability of IPv6," DeLong said.
DeLong added that many big-name websites are working on IPv6 behind-the-scenes even though they didn't want to publicly commit to supporting IPv6 by June 6, the World IPv6 Launch Day deadline. For example, Amazon in May announced expanded IPv6 support for its Elastic Load Balancer. "Amazon's networking group is putting some effort into making its services IPv6 capable even if Amazon.com isn't ready yet," DeLong said.
Similarly, Apple is making improvements in its IPv6 support in OS X Lion but isn't yet supporting the new protocol on its popular Apple.com website or its iTunes or App Store services. "Apple is running IPv6 internally throughout its internal corporate engineering network," DeLong said.
IPv6 proponents are hoping that a successful World IPv6 Launch Day will encourage Apple, Amazon and other laggards to ramp up their IPv6-related efforts.
"There aren't as many IPv4 addresses as there are people on the planet," Daigle points out. "More and more companies are waking up to that fact and wondering how they are expected to cope with IPv4 in terms of buying IPv4 addresses or installing increasingly complex network address translators or deploying IPv6."
DeLong said there's no doubt that IPv6 will become increasingly important for website operators to support. "We've seen a 5X to 6X increase in IPv6 traffic in the last week on our own backbone network," DeLong said, pointing out that Hurricane Electric has the Internet's most interconnected IPv6 backbone. "The IPv6 traffic is only going to go up from here."
World IPv6 Launch Day "is probably the first time we're going to see the amount of IPv6 traffic go up significantly and stay that way," agreed Bob Hinden, a Check Point fellow and one of the developers of IPv6 at the Internet Engineering Task Force. "I think we'll see it spike as more content is turned on."