Broadcom set-top silicon touts downstream channel bonding, advanced coding

Thu, 01/04/2007 - 6:48am
Jeff Baumgartner, CED

Broadcom Corp. has unveiled the BCM7118, an integrated chipset for digital cable set-top boxes that supports a raft of new features, including downstream channel bonding, more efficient encoding, and downloadable security.

With an eye toward IP-delivered video via the set-top, the chip includes DOCSIS/EuroDOCSIS 2.0 capabilities, but will also be able to handle downstream channel bonding, a feature of the newer DOCSIS 3.0 specifications.

While DOCSIS 3.0 is being outfitted to support channel bonding in the usptream and downstream, some pre-3.0 implementations will fuse multiple DOCSIS 2.0 downstream channels. Broadcom said its downstream channel bonding implementation in the BCM7118 will be compatible with DOCSIS 3.0.

On the compression front, the new chip will also support the MPEG-4 part 10 and VC-1 codecs, as well as the widely-deployed MPEG-2 platform.

Broadcom has also equipped the chipset to support the DOCSIS Set-top Gateway (DSG), a CableLabs-specified signaling platform, as well as a Downloadable Conditional Access System (DCAS), a separable security function viewed as a potential replacement for the CableCARD being undertaken by Polycipher, a non-profit company backed by Comcast Corp., Time Warner Cable and Cox Communications.

Broadcom noted that the chipset houses an integrated secure processor, and that each chip programmed by the company will contain a permanent, unique identification and configuration. 

The company said the chipset was developed using guidelines set by cable's Next Generation Network Architecture (NGNA). Many of the chipset features cited by Broadcom also fall in line with features expected to be found in Comcast's forthcoming "RNG" product family, which will include low-end digital set-tops, as well as more advanced HD/DVR combinations.

In fact, Broadcom is using the BCM7118 as the baseline for two reference designs: the BCM97118RNG (a low-cost, entry-level, all-digital box design), and the BCM97118 (integrated hard drive for mutli-room DVR applications).

"We have integrated a tremendous amount of state-of-the art technology into the new BCM7118 cable set-top box chip based on cable operator and customer feedback regarding what they need to compete in their end markets," said Daniel Marotta, SVP and GM of Broadcom's Broadband Communications Group.

Broadcom said the new chipset is being offered in sample quantities to "early access customers."


Share This Story

You may login with either your assigned username or your e-mail address.
The password field is case sensitive.