Arris CTO: What's Next for DOCSIS?
Extending the life of DOCSIS and HFC, of course, would be good news for vendors in the sector that bank on those technologies and the revenues that future upgrades bring through the door. Although the ideal path, at least from a PHY layer perspective, would be to enable these new capabilities with modules that can snap into existing gear, such upgrades are likely to also require new network equipment (including CMTSs, nodes and active devices), as well as modems that can support the new, proposed upstream split and extended spectrum for the downstream.
If one or both of the ideas have legs, it could eventually make it up to the CableLabs level. The organization has made no announcement about a formal initiative. However, at a panel in June, CableLabs principal architect Doug Jones hinted that the organization was working on a plan to get cable operators to symmetrical 1-Gig based on an N+5 environment.
And the crystal ball says...
Cloonan said it's too hard to predict when either option under study might reach commercial status. But he guesses that the mid-2020s is a possibility, though that target will likely move based on operator requirements and how network traffic patterns fluctuate in the coming years.
For now, Arris is running tests (mostly as lab simulations, as it originally did with FDX and DOCSIS 3.1) and has done some early product design work. Cloonan said Arris will have some of that handiwork on display at this week's Society of Cable Telecommunications Engineers (SCTE) Cable-Tec Expo in Atlanta.
And if there's anyone qualified to opine on the future of DOCSIS and the HFC network, it's Cloonan. After all, he's been front and center and a major engineering force in driving the direction of DOCSIS's past, present and future, and ensuring that cable stays a few steps ahead of the capacity curve.
Cloonan, who was with Bell Labs for 17 years working on technologies like ATM switching and high-speed routing before pivoting to cable, was involved in the early, 1.0 days of DOCSIS at Cadant, a cable modem termination system (CMTS) startup that Arris acquired in 2002. Since then, he's been shepherding the spec to 1.1, 2.0, 3.0, 3.1, and FDX… and likely will help influence where it goes next.
HFC or FTTP? The debate that never dies
Arris is also pursuing what could be next in HFC's evolution amid the ongoing debate on when -- rather than if -- MSOs will just make the leap to fiber-to-the-premises. Though Altice USA is an outlier among domestic operators, most US cable operators continue to upgrade HFC networks incrementally as they push fiber closer to the home. (See Altice USA Lights Up FTTH Service in Long Island.)
Cloonan says the debate centers on the economics and the business case, noting that the company's own studies continue to show that switching to PON on a per-subscriber basis still costs a lot more than it does to enhance and upgrade capacity on existing HFC networks.
Greenfield scenarios are a different story. "If you're putting something new in the ground, you should probably put fiber," he said.
— Jeff Baumgartner, Senior Editor, Light Reading