MaxLinear touts 10-Gig speeds with 'Puma 8' DOCSIS 4.0 chip

MaxLinear claims its new Puma 8 DOCSIS 4.0 modem chipset can deliver downstream speeds of greater than 10 Gbit/s on DOCSIS 3.1 hybrid fiber/coax (HFC) networks as well as HFC networks that are upgraded to the full DOCSIS 4.0 specifications.

The chipmaker is touting that achievement more than two months after MaxLinear introduced the Puma 8, a chipset that is expected to reach commercial availability later this year.

The Puma 8 utilizes the extended spectrum DOCSIS/frequency division duplex (FDD) flavor of DOCSIS 4.0, which envisions an HFC network built out to 1.8GHz while keeping upstream and downstream traffic operating in separate, dedicated spectrum. The other D4.0 option – Full Duplex (FDX) – is designed to run on HFC networks built to 1.2GHz and utilize an FDX band that allows upstream and downstream to operate in the same block of spectrum. Comcast's DOCSIS 4.0 deployment strategy is primarily focused on FDX.

MaxLinear said the Puma 8 can deliver downstream speeds in excess of 10 Gbit/s and upstream speeds up to 7 Gbit/s when the chip is paired with MaxLinear's DOCSIS 4.0 ultra high-split upstream programmable gain amplifier (PGA), which takes advantage of six OFDMA channels in the 108MHz-684MHz band and 1 OFDMA channel in the legacy 5MHz-85MHz band.

Related:MaxLinear joins Broadcom in DOCSIS 4.0 chip race with 'Puma 8'

Puma 8 for 'ultra' DOCSIS 3.1

But, as Light Reading reported last month, MaxLinear has also adapted the Puma 8 (with a minor board change that does not include the upstream PGA) to generate 10-Gig downstream speeds on DOCSIS 3.1 networks – something MaxLinear refers to as "ultra DOCSIS 3.1." Those loftier downstream speeds are enabled through the support of five OFDM (orthogonal frequency-division multiplexing) channels, rather than the two OFDM channels supported by current-generation DOCSIS 3.1 modem chipsets.

The elimination of that PGA would also ensure that the enhanced D3.1 version of the Puma 8 costs only "incrementally" more than MaxLinear's legacy DOCSIS 3.1 Puma 7 chip, Will Torgerson, VP and GM of MaxLinear's Broadband Business Unit, said in a recent interview.

With that in mind, MaxLinear reasons that the DOCSIS 3.1 option for the Puma 8 puts cable operators in position to deliver PON-like speeds without the costs for a full-scale DOCSIS 4.0 network upgrade. Or, operators can run the Puma 8 on DOCSIS 3.1 networks as an interim step toward future D4.0 upgrades.

By delivering speeds that rival fiber, the Puma 8 "positions our MSO partners to deliver ultra-fast broadband with smart capital expenditure, elevating the home connectivity experience for consumers today and into the future," Torgerson said in a statement.

Related:How Broadcom and MaxLinear will push the limits of DOCSIS 3.1

MaxLinear plans to show off the Puma 8, including its upstream-enhancing PGA capabilities, at next week's CES event in Las Vegas.

Update: MaxLinear said the ultra D3.1 version of the Puma 8 will support upstream speeds up to 2 Gbit/s. The company is currently sampling the Puma 8 with partners, including some that will show their designs at CES. Meanwhile, MaxLinear also plans to submit a reference platform powered by the Puma 8 to CableLabs for DOCSIS certification testing, a company official said.

DOCSIS silicon action heating up

Broadcom, MaxLinear's primary competitor in the DOCSIS arena, is taking a similar approach with a new chip called the BCM3392, according to industry sources. Broadcom hasn't announced any details about the BCM3392, but sources say Broadcom's upgraded D3.1 modem chip will support four 192MHz-wide OFDM channels and eventually succeed the BCM3390 (Broadcom's current-gen D3.1 modem chipset). Broadcom and Comcast are also collaborating on "unified" chipsets that support both flavors of D4.0.

Last fall, MaxLinear revealed that three DOCSIS modem/gateway makers – Askey, CommScope and Hitron – have signed on as "early access partners" for the Puma 8.

Related:MaxLinear: Comcast stole our FDX ideas

MaxLinear hasn't announced any cable operator commitments for the Puma 8. However, recent court documents show that, back in July 2021, MaxLinear signed an agreement with Charter to develop cable modems compatible with DOCSIS 4.0. Under its multi-year network evolution plan designed to deliver multi-gigabit downstream speeds and 1 Gbit/s in the upstream, Charter intends to upgrade about 35% of its HFC network to DOCSIS 4.0. About 85% of Charter's HFC footprint will move to a distributed access architecture (DAA) paired with a virtual cable modem termination system (vCMTS).