DOCSIS 3.1: A Calm Before the D4 Storm

MSOs may be split on the future of DOCSIS 4.0, but many continue to invest in their DOCSIS 3.1 deployments even as they consider future strategies for 10 Gbit/s symmetric offerings.

Distributed access architecture and network virtualization coupled with software-defined networking are gaining industry-wide adoption, but operators are split between Full Duplex DOCSIS (FDX) and Extended Spectrum DOCSIS (ESD). (See Chaos Cuffs Cable's Access Network Players.)

Comcast is behind FDX. This approach is designed to allow upstream and downstream traffic on one block of spectrum but needs "node+0" upgrades that pull fiber deeper into the network and cut out amplifiers between premises and node. Other providers disagree. Some engineers say ESD is much a simpler way to grow capacity as it splits off spectrum that's dedicated to traffic going up- or downstream. It also doesn't need those node+0 upgrades or extra fiber.

This stalemate between the two technologies has caused paralysis, Alan Breznick, cable/video practice leader at Light Reading, told Jeff Baumgartner.

The ecosystem of suppliers is not big enough or profitable enough to support both technologies, Baumgartner reported.

DOCSIS 3.1 in full deployment mode
This has not affected DOCSIS 3.1 roll-outs. After all, MSOs began these deployments years ago, and some completed these infrastructure projects in late 2018 or earlier this year. The technology and product sets were successful very quickly, said John Romagnoli, senior director of Commercial Products at Atlantic Broadband in an interview with Broadband World News. Atlantic Broadband acquired Metrocast in Connecticut, which had a DOCSIS network. Soon most, if not all, the provider's DOCSIS 3 markets will be upgraded to D3.1, driven by a need for services such as hosted voice, cloud-based applications and symmetric use cases.

More critically, D3.1 empowered Atlantic Broadband and other MSOs to create sustainable, profitable business models that serve customers, he added. The technology did not displace fiber; it complemented that more expensive infrastructure by allowing the operator to offer a service that was both less expensive than fiber and faster than DSL, Romagnoli said.

"When we talk about 3.1 we tend to talk about 1-gig and 1-gig deployments, and while that's extremely important and newsworthy, what DOCSIS 3.1 also allows us to do is expand all the other speeds in the portfolio. It allows us to give our business and residential customers a much wider array of bandwidth solutions that best-match the problems they're trying to solve and that creates a stickier product," he noted. "It makes for a better customer experience and a customer who stays. Those are my two measures of success over the past few years of deployment."

As needs for capacity and bandwidth grow, they can move to fiber -- which makes up Atlantic Broadband's infrastructure, Romagnoli said.

On the other hand, in June service provider Otelco told prospective customers it was moving away from a fiber-only strategy to serve a greater number of subscribers faster. Otelco will spend about 20% of its $5 million investment in Alabama on non-fiber infrastructure such as DOCSIS and copper-based technologies, including VDSL or Gfast, wrote Trevor Jones, vice president of Marketing, Sales and Customer Service, in a blog. (See DOCSIS 3.1 Gains New Ground.)

"Cable TV systems have the capacity to provide considerably more bandwidth than DSL, and can even provide gigabit-level download speeds if we move to an all-digital television network and upgrade the system to the new Gig capable DOCSIS 3.1," he said. "Ultimately… knowing we could get so much more out of the cable system, we knew the priority for Fiber to the Home deployment has to be in DSL systems where we have less growth potential for bandwidth on the existing network. On the other hand, we're sure our cable customers will see dramatic improvements by this time next year."

The fiber fixation
Some operators are voicing plans to go full-fiber, with no public mention of further DOCSIS iterations beyond D3.1.

Altice USA expects its entire footprint will be 1-gig ready by the end of this year, said CEO Dexter Goei in the company's Q2 earnings call in July. While it expects to complete its D3.1 deployment across the MSO's Optimum footprint in the Tri-State New York area by year-end, in the near-future Altice USA wants to "fiberize" all its 5-million-home Optimum area, Goei said.

"We are currently at about 300,000 homes ready for service and about a million homes cabled or passed today which will then become obviously ready for service as we continue to drive our investment," he said. "We've always been very clear that we are upgrading and the interim, our Optimum footprint to 1 gig on DOCSIS 3.1. So in terms of competition relative to 1-gig product, we will be delivering that competition before year-end. Secondly, I think the most relevant proof point relative to our [FTTH] is that we believe we're going to be 10 gig-ready as early as the first half of next year. So we will market a 10-gig product. We're expecting to be able to market at 10-gig product up and down within the first half of 2020."

For its part, Shenandoah Telecommunication is using a combination of D3.1, FWA and fiber to serve customers, said Dave Heimbach, executive vice president and chief operating officer during its second-quarter 2019 earnings call. More than 80% of its cable homes are capable of speeds up to 1 Gbps, he said. The provider also launched Glo Fiber, which will offer residential customers multi-gigabit symmetrical speeds via an all-fiber network, Heimbach added.

"Fixed wireless broadband deployment is a natural extension of Shentel's strategy in its less densely populated service areas, and this spectrum will be foundational to this emerging means for last-mile broadband delivery," he said, according to Seeking Alpha. "Total capex related to fixed wireless in 2019 is expected to be approximately $20 million, with $17 million for spectrum payments and $3 million for related equipment."

Shentel expects to launch the FWA offering in the second half of 2020 and target rural areas next to its existing cable and ILEC footprint, as well as its planned FTTH home markets in the Mid-Atlantic area, said Heimbach. Capex spending for the year includes $33 million for legacy cable systems, including D3.1 upgrades, he said. "We still expect to complete the DOCSIS 3.1 upgrades and digital conversions by the end of the year to enable gigabit speeds across all of our cable networks by 2020," said Heimbach.

The company plans to launch a carrier-grade LTE standards-based, fixed wireless broadband offering, leveraging this newly acquired license spectrum sometime in the back half of 2020. The service will target rural areas adjacent to our existing cable and ILEC footprint and our planned fiber to the home markets in the Mid-Atlantic region.

Related posts:

• FTTP or Next-Gen HFC? It's Complicated
• Why FTTH May Trump Fiber Deep for Cable
• DOCSIS Is Go for '4.0'

— Alison Diana, Editor, Broadband World News. Follow us on Twitter or @alisoncdiana.