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 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 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.

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.

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.

“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.”

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.

source: ciscozine.com