About 94.5% of IPv4 address space has been allocated as of Sept. 3, 2010, according to the American Registry for Internet Numbers (ARIN), which delegates blocks of IPv4 and IPv6 addresses to carriers and enterprises in North America. Experts say IPv4 addresses could run out as early as this December but will certainly be gone by the end of 2011.
ARIN and other Internet policymakers are urging Web site operators to deploy IPv6 by Jan. 1, 2012, or risk disenfranchising users with IPv6 addresses by providing them with slower, less-reliable service.
Cisco's disclosure of its IPv6 testing efforts came on the same day that the Obama Administration held its first-ever event focused on the IPv6 issues.
Cisco says it is being prudent by taking a careful, testing-based approach to IPv6 deployment on its Web site.
"IP addresses are used by applications in a variety of ways, and only by exercising the code can we find them all," Townsley says. "The Internet is in a transition phase, and while pressure is on due to the looming IPv4 free pool run-out in 2011, we still have some time left to see how the network and applications respond, monitor traffic, and get ready for the day when we really turn the traffic up by offering an IPv6 address to the Web site when someone types in http://www.cisco.com."
Townsley said Cisco is experiencing a very small amount of IPv6 traffic. "We want to run in alpha-test mode for a while to work out any bugs in the server applications and monitor the situation. This is the good thing about starting now, as we can afford to stage the bring up and watch it carefully," he adds.
The IPv6 development and testing process that Cisco is engaged in now will be more common next year, as pressure mounts for Web site operators such as federal agencies to support IPv6 on their public-facing Web sites. Other industry laggards on IPv6 include Yahoo and Twitter.
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