Brzozowski was speaking here at the IPv6 Summit at the Cable Show, presented by the National Cable & Telecommunications Association and sponsored by Arris. The track featured experts from both inside and outside the cable industry.
"There was a sustained uptick in various types of IPv6 traffic," Brzozowski said, with Comcast's native IPv6 traffic increasing sixfold during the event and then 10-fold after World IPv6 Day.
But there's still lots of work to be done, both in refining the IPv6 software and systems for content and network providers and getting the protocol embedded into CE devices, speakers noted.
Turner Broadcasting System activated IPv6 for CNN.com on World IPv6 Day, and "the only complaint we got was from somebody who couldn't access CNN via IPv6 only. That's a good problem to have," said Sam Gassel, Turner technology fellow for digital media technologies.
"What's available in the market today is ready for a low-volume test," Gassel said. "Is it ready for a high volume? We'll find out next time."
Internet providers, content producers and equipment providers must adopt IP version 6 because ISPs will run out of their IPv4 addresses as early as late this year or the beginning of 2012. IPv6 provides a cosmically large number of unique address, roughly 2 to the 128th power, versus about 4.2 billion with IPv4.
World IPv6 Day was a 24-hour global test of the protocol that spanned June 7 and 8 in the U.S., aimed at promoting IPv6 adoption and discovering critical technical issues.
"It was about websites turning on IPv6 on their front door for 24 hours," said Phil Roberts, technology program manager of The Internet Society, which sponsored World IPv6 Day. "It was not about turning off IPv4."
Well more than 1,000 websites participated, including Google, YouTube, Facebook, MSN, AOL and Yahoo, Roberts said. Roughly two-thirds of the 400 sites ISOC was monitoring left IPv6 on after the event, he added.
IPv4 and IPv6 are fundamentally incompatible, which means there will be a long period of "dual-stack" operation as usage of IPv4 fades away and IPv6 increases.
During the June 7-8 World IPv6 Day period, Comcast did not see an increase in calls to its customer-support line and "we literally had one e-mail support request," Brzozowski said. "The joke I used yesterday was it was a waste of 37 hours of not sleeping for me."
In advance of the event, Comcast proactively sent out several hundred upgrade kits to subscribers running older versions of Mac OS X that have a bug that makes them respond improperly to sites running IPv6. "We said, ‘Here you go -- you should really upgrade," Brzozowski said. "We need to make sure people with broadband have IPv6."
Time Warner Cable had hundreds of trouble calls on World IPv6 Day but two-thirds were questions about the protocol was and what the test involved, said Lee Howard, Time Warner Cable director of network technology.
"It was not even a blip on the radar screen," Howard said. TWC had 564 addresses tested on the day of the test, and only seven addresses failed to properly respond to IPv6.
Comcast kicked off IPv6 trials in early 2010 and spent the last few months actively gearing up for World IPv6 Day. The MSO made Comcast.net content available over IPv6 with the assistance of Akamai Technologies.
At the Cable Show, CableLabs in the CableNET pavilion is demonstrating carrier-grade network address translation, which allows ISPs to let many users share IPv4 addresses to access Internet content once there aren't enough IPv4 addresses to go around. In addition, an exhibit developed by Comcast and Time Warner Cable will showcase IPv6-compatible consumer electronics.
"We still see challenges with certain advanced applications with carrier-grade NAT... but we are very close," CableLabs project director of network protocols Chris Donnelly said. "Three months after ARIN runs out [of IPv4 addresses] you'll see carrier-grade NAT show up in networks."
Donnelly noted that CableLabs will host another IPv6 interoperability event this fall for equipment providers, from Sept. 19 to 30, at its headquarters in Louisville, Colo.