Cisco To Take DOCSIS 3.0 Modems Over 300 Mbps


Cisco Systems is developing a cable modem that will use Broadcom’s recently announced DOCSIS 3.0 silicon to bond together eight downstream channels – letting cable providers, theoretically, pump Internet content down to subscribers at more than 300 Mbps.

The vendor hopes to submit the first DPC3212 cable modem to CableLabs for qualification in the first quarter of 2009. The unit is expected to be shipping in volume by the middle of 2010, Cisco cable solutions marketing manager Ben Bekele said.

The DPC3212 will be an embedded multimedia terminal adapter (eMTA), with support for two phone lines, and provide data rates of more than 300 Mbps downstream and about 120 Mbps upstream.

According to Bekele, the idea with the eight-downstream-channel devices is to let cable operators future-proof their installed base of DOCSIS modems. So while a cable operator wouldn’t necessarily introduce a 300-Mbps Internet tier initially, that latent capacity would be available down the line.

“As long as the cost is comparable, you’ll see a lot of operators gravitate toward 8 by 4,” he said, referring to a cable modem that provides eight downstream and four upstream channels.

He noted, however, that right now Cisco is not exactly sure how the cost of the DPC3212 cable modem would compare with current DOCSIS 3.0 models.

The forthcoming unit would be among the first to use Broadcom’s BCM3380 DOCSIS 3.0 modem chip. Cisco also plans to incorporate Broadcom’s DOCSIS 3.0 physical layer (PHY) component in its next-generation cable modem termination system (CMTS).

Cisco is currently shipping two DOCSIS 3.0 customer-premises products, the DPC3000 cable modem and DPC3202 eMTA, which both use Texas Instruments’ Puma 5 chip set.

The driving force in the future for higher-speed broadband will be video over DOCSIS -- whether that’s managed video content or unmanaged content going over the top, Bekele said.

Cisco has predicted that the annual bandwidth demand on the world's Internet networks will nearly double every two years -- reaching 522 Exabytes annually in 2012 (the equivalent of 250 million DVDs) -- and that half of that will be video traffic.

“That’s going to make it more likely that operators will push the tiers higher,” Bekele said. “That ability to leapfrog to eight channels definitely becomes an advantage.”