February 24, 2009

Looking Beyond DOCSIS 3.0

By Linda Hardesty

DOCSIS 3.0 won't be nirvana for the cable industry, according to the opening keynote speaker today at a Light Reading DOCSIS 3.0 conference in Denver.

"We're still limited in the upstream channel," said Rouzbeh Yassini, CEO of YAS Broadband Ventures. "Good job, but no cigar yet. Even 35 Mbps upstream is still not enough."

Yassini said 100 Mbps shared downstream speeds achieved with DOCSIS 3.0 are peaks, not constants, and today's applications need constant bit rates.

"If you want to have multiple services and high definition (HD) video, it's not the ultimate answer as far as our network capacity goes," Yassini said. "Constant HD needs a constant bit rate."

Sometimes called the "godfather" of DOCSIS for his role in shepherding the original specification, Yassini stirred things up a bit with his comments.

"I thought Rouzbeh (Yassini) was a bit harsh in terms of the upstream," said Michael Cookish, a senior director of CMTS product management at Motorola. Cookish agreed that 100 Mbps upstream speeds would be demanded in the commercial services arena within three to five years, but that it would be doable.

To reach the necessary upstream speeds, Cookish recommended: (1) migrate to DOCSIS 2.0; (2) add upstream channels; and (3) split nodes.

As for why consumers will need such high speeds, next generation broadband applications were mentioned, including security systems, building temperature controls and digital signage.

Yassini also stressed user interfaces. "It's not about the pipe; it's about the collective package, the user interface," he said. (For more about the importance of the interface, click here.)

"As an industry, we are lagging on bringing the user interface," Yassini said. "Meanwhile, some software companies are doing a great job."

DOCSIS 3.0 Spec

While some are already looking beyond DOCSIS 3.0, CableLabs continues to work on its specification. Matt Schmitt, director of DOCSIS Specifications at CableLabs, said the focus is on stability. (For more, click here.)

"With a spec as large and complex as DOCSIS 3.0, we put a freeze on new feature development," Schmitt said. "We want to see DOCSIS 3.0 products out in the field as soon as possible. We're finding that it's not capped at 160 Mbps. We think there's a lot of life there."

- Linda Hardesty

Read more news and analysis on Communications Technology's Web site at www.cable360.net/ct/news/.