SCTE: Cable CTOs Dish On Bandwidth


Philadelphia—Even as cable operators prepare to roll out higher-speed DOCSIS 3.0 “wideband” broadband service, they’re also fine-tuning ways of curbing the small percentage of subscribers who consume far more than their fair share.

Tony Werner, Comcast’s executive vice president and chief technology officer, referred to the operator’s ongoing trials to manage bandwidth based on individual usage rather than targeting specific protocols.

“We reached out IETF, MIT, Google, several of the vendors, BitTorrent… and started going through, what are the ways to best manage the network?” he said.

Werner spoke on the CTO panel here at the Society of Cable Telecommunications Engineers’ Cable-Tec Expo conference, which was moderated by Multichannel News columnist Leslie Ellis.

Comcast was criticized by Internet activists for throttling back peer-to-peer applications that use the BitTorrent protocol, complaining that the practice violated the Federal Communications Commission’s policies ensuring open access.

Now Comcast is testing three different “protocol-agnostic” network management systems—in Chambersburg, Pa., Warrenton, Va., and Colorado Springs, Colo.—to arrive at a usage-based means of managing bandwidth.

Comcast’s plan is to identify the 2% or 3% of customers who over the last hour or two have consumed more than 50% of the capacity on the network, Werner said. Those heavy users are then given lower priority and will have their bandwidth limited for a temporary period of time.

However, Werner said, “even those who go to that lower state will be above DSL. So it’s not terrible.”

Who are the worst offenders? Werner said some subscribers have used “in the 3-plus terabyte range—that’s not uncommon. They did nothing but download movies constantly.”

“You could watch movies for 12 years in the amount of data they download in one month,” Werner added.

Cox Communications senior vice president of engineering and CTO Chris Bowick trotted out some numbers of his own. Two Cox subscribers in particular stood out in the last 30 days.

One customer used 681 gigabytes of upstream bandwidth capacity in one month. His upstream speed is 2.3 Mbps, which means he almost hit his theoretical maximum possible upload capacity of 710 gigabytes, Bowick said: “In essence, he’s maxed out his upstream for the entire period.”

Translated into movies or songs, 681 gigabytes would be 170,000 uploaded songs and 888 hours of video.

On the downstream side, a different Cox subscriber pulled down 1.5 terabytes of data in the last 30 days, again almost hitting the theoretical maximum of 1.6 or 1.7 terabytes. That much data would be the equivalent of 377,000 songs or 188 DVD movies.

Quipped Ellis: “That’s a lot of porn.”

On the DOCSIS 3.0 front, Cox plans to start deploying wideband service in the third quarter in “strategic markets, markets that will require those speeds,” Bowick said.

“There’s no need to launch DOCSIS 3.0 ubiquitously unless you need those speeds from a competitive perspective,” Bowick said. “We’ll roll out DOCSIS 3.0 in a very targeted way this year and into next year.”

Verizon Communications now offers FiOS Internet service with 50-Mbps downloads to 10 million households in 16 states.

Werner said Comcast has gained some insight into deploying DOCSIS 3.0 in its initial Minneapolis/St. Paul market. For example, some older DOCSIS 2.0 modems needed to be updated to be compatible with the 3.0 CMTSs.

“All in all, though, it’s been relatively straightforward,” he said, adding that “50 megabits is probably the speed we’ll go out the door with” in other markets. [Comcast spokeswoman Jenn Khoury on Thursday said the operator has not yet decided on specific bandwidth tiers for other market rollouts.]

Werner did acknowledge that there’s a marketing challenge MSOs will have in attempting to convey the advantages of wideband cable modem service.

Besides “very fast downloads, there are three or four others in the pipeline that we’re investigating,” Werner said.

But he pointed out that consumers haven’t had trouble using the full capacity of their connections: “The Internet community, the entrepreneurs… have found uses for the bandwidth.”