Comcast and Time Warner Cable added their names to the international list of companies that will participate in World IPv6 Day, during which service providers will engage in a readiness trial for switching over to the next generation of the Internet Protocol (IP).

Also announcing their participation were SoftLayer Technologies and Rackspace Hosting Click here!. World IPv6 day, the first global scale 24-hour test of IPv6, will be June 8. Sponsored by the Internet Society, the test will enable the industry to test IPv6 readiness and prepare for seamless full deployment.

"World IPv6 Day is important to further the deployment and widespread enablement of IPv6," said John Brzozowski, chief architect for IPv6 and distinguished engineer at Comcast. "Being able to test our infrastructure at scale and verify our customers' experience is essential to seamless enablement."

"We're working hard to make IPv6 available to our customers," said Lee Howard, director of network technology for Time Warner Cable. "All transitions have risks, and we're glad to be working together to minimize those risks with this significant test."

Other organizations that have already announced their participation include Google, Yahoo, Akamai, Limelight Networks, Cisco Systems, Juniper Networks, Mozilla and Facebook.