Cox, GCI dish on DOCSIS 4.0 testing, deployment plans

Executives from Cox Communications and Alaskan operator GCI told Fierce their DOCSIS 4.0 deployments will start with targeted rollouts in key markets and offered an update on where their efforts to test the technology stand.

Both companies are set to delve into their DOCSIS 4.0 plans in greater detail during FierceTelecom’s free, virtual Broadband Technology Summit next week. They will take part in a panel discussion on Monday morning focused on “Laying the groundwork for 10G: DOCSIS 4.0, DAA and Beyond.”

Ahead of the event, though, Cox Chief Access Scientist Jeff Finkelstein and CGI VP Engineering and Architecture Victor Esposito shed more light on why they’ve chosen to pursue the extended spectrum variant of DOCSIS 4.0 (known as ESD) and how they plan to proceed with rollouts.

Finkelstein told Fierce it chose ESD for a number of reasons, pointing to scale benefits given many other operators are also pursuing the technology. He added it’s also simpler in some ways, extending Cox’s existing operating model for spectrum management by continuing to use dedicated upstream and downstream spectrum. The other DOCSIS 4.0 option, known as full duplex or FDX, meanwhile “creates a whole new paradigm of operational support requiring new tooling and training for our technicians and agents.” That’s because FDX aims to enable simultaneous upstream and downstream transmissions over the same spectrum.

Cox is currently lab testing DOCSIS 4.0-compatible passive and active equipment, as well as Remote-MAC PHY nodes and cable modems, Finkelstein said. Thus far, performance has “met or exceeded our expectations” and Cox is “working on test equipment for D 4.0 operational needs.”

Esposito said GCI, which is likewise pursuing ESD, is also testing passive DOCSIS 4.0 equipment such as cables, connectors and coaxial splitters. While it’s not yet testing active equipment, it plans to do so “once it becomes more stable/available,” he said.

Both Finkelstein and Esposito said they’re not worried about market fragmentation between ESD and FDX. The latter noted the two options “are complimentary in many ways, and just feature differences in DOCSIS. While this has caused some distraction, I believe it will ultimately lead to a better product at the end of the day. While we are taking the ESD route, as many other operators are, I can see a day when we will incorporate a version of FDX, but that will be much further down the road.”

Esposito continued that GCI is looking to start rolling out DOCSIS 4.0 once equipment becomes available and is targeting a 2025 timeline to start. He said it plans to start with a deployment in Anchorage before extending the technology to the rest of its statewide HFC network.

For Cox’s part, Finkelstein said it hasn’t announced customer deployment dates, but plans to proceed with a targeted rollout of the technology across its footprint.

Interestingly, Finkelstein agreed with a recent comment from an Altice USA executive that fiber is the “logical end state” of HFC. However, he argued “we still likely have 20+ years to meet the majority of customer demands using coaxial networks and DOCSIS.”

“DOCSIS has a long and useful life ahead,” he concluded.