Cable modems: OEMs take their pick

Motorola has chosen a Texas Instruments chip for its next generation cable modem design, while Scientific-Atlanta, Tellabs and Thomson Multimedia have opted for devices from Broadcom.

Motorola’s next-generation cable modem, the SB4220, is to be based upon Texas Instruments Data Over Cable Service Interface Specification (DOCSIS) 1.1 silicon and software. It will also implement the new DOCSIS 2.0 advanced time division multiple access (A-TDMA) physical layer standard.

Broadcom’s cable offerings on the other hand, are to be used in cable modems from Scientific-Atlanta, Tellabs and Thomson Multimedia.

The Scientific-Atlanta and Thomson cable modems plan to use the Broadcom BCM3345 chip, a single-chip DOCSIS/ EuroDOCSIS 1.0 and 1.1-capable modem.

The Tellabs modem and an additional Scientific-Atlanta device are to use the BCM3351, a two-line Voice over Internet Protocol (VoIP) cable modem chip that also supports HomePNA wireline home networking and 802.11b and Bluetooth wireless technologies.

Broadcom says that since its cable modem operates independent of the physical layer, it is fully scalable to meet the new DOCSIS 2.0 physical layer specification.

Editor’s note: DOCSIS 2.0 builds upon the capabilities of DOCSIS 1.0 and DOCSIS 1.1 and adds throughput in the upstream portion of the cable plant – from the consumer out to the Internet – creating a network that has 30 Megabit/s capacity in two directions. The specifications for the DOCSIS 2.0 standard were completed at the end of last year.

DOCSIS 2.0 is compatible with DOCSIS 1.0 and 1.1 cable modems (CMs) and cable modem termination systems (CMTSs).