First DOCSIS 3.1 Modems Will Have 4-5 Gbps Potential

ATLANTA – SCTE Cable-Tec Expo 2013 -- DOCSIS 3.1 is being designed to scale up to 10 Gbps in the downstream, but the first wave of modems that adhere to the specs should be capable of reaching almost half of that potential.

The first DOCSIS 3.1 modems will be hybrids that support both DOCSIS 3.1 and DOCSIS 3.0 spectrum, and will be able to handle both simultaneously. The DOCSIS 3.0 side will carry a minimum requirement of bonding 24 downstream QAM channels and 8 upstream QAM channels, alongside a DOCSIS 3.1 minimum that calls for the ability to tie in two channels/blocks orthogonal frequency-division multiplexing (OFDM) at 192MHz-wide each, and two 96MHz-wide channels for the upstream.

Those are the baseline requirments and operators will later decide how and when to turn up that capacity, but when fully-loaded, that 3.0/3.1 mix will be able to handle  max downstream speeds of 4 Gbps to 5 Gbps, and 1.5 Gbps in the upstream right out of the chute, Matthew Schmitt, CableLabs’s director of DOCSIS, explained here in an interview.

Considering that cable operators have yet to introduce high-speed Internet tiers that advertise anything beyond 500 Megabits per second  downstream using DOCSIS 3.0 (Com Hem of Sweden, for example, unleashed a 500-Meg offering earlier this year), the first set of hybrid 3.1 gear should have plenty of legs.

Presuming things proceed at the expected pace, those modems should start to show up by late 2014, enabling operators to start putting the new CPE in the field by sometime in 2015, if they can swallow the price. It’s expected that introduction of cable modem termination system (CMTS) gear that supports D3.1 will follow the debut of the modems, giving MSOs and opportunity to seed the market for the new specs.

The core DOCSIS 3.1 product interface specifications, which will provide silicon maker and cable modem and cable modem terminations system vendors the blueprint required to start building products, will be released by the end of October, Schmitt said here on Monday at the a day-long DOCSIS 3.1 Engineering Pre-Conference Symposium. In a separate interview, Schmitt said the DOCSIS 3.1 networking management specs should be complete sometime in 2014.