When it comes to delivering new speeds and services, cable operators tend to opt for conservative, incremental steps rather than wholesale upgrades and replacements. They often follow the path of least resistance and go with the technologies they know, rigorously tested and standardized, before they make any leap forward. That behavior has served them extremely well and made them by far the largest broadband providers in the North American market.
So, it was very interesting to see Mediacom’s announcement of its 10G Smart Home in Ames, Iowa, as cable operators have generally shied away from public demonstrations of forward-looking capabilities of their broadband networks. The partnership with CableLabs and NCTA showcases bandwidth-intensive applications that could ultimately drive the need for 10G speeds, including 8K video, a light field display, as well as VR and AR applications, eSports, and telemedicine applications.
Although the focus is on these and the other potential applications that will drive continued demand for more bandwidth from residential broadband networks in the future, looking under the hood shows that the adjustments required in the network to deliver these services aren’t really that far off. In fact, the demonstration is notable for the fact that these bandwidth levels can be achieved with existing HFC plant.
According to Light Reading, the 10G Smart Home is fed by a DOCSIS 3.1 network that has been upgraded to 1.2GHz of downstream spectrum and a range of 5-204MHz of upstream spectrum through a high-split architecture. The network is also based on a node plus zero approach, meaning that fiber has been deployed deep into the network, obviating the need for additional amplifiers between the last node and the home. Mediacom’s network in Ames is node plus two. Average cable systems in North America run anywhere from node plus four to node plus six, so Mediacom started with a bit of an architectural advantage when it comes to amplifier cascades relative to other cable operators.
The 10G smart home is also based on a distributed access architecture (DAA) using remote PHY devices from both CommScope and Casa Systems, which also announced that its new DA2200 node was being used. The new RPDs support high-split architectures and also OFDM and OFDM-A subcarrier channels to deliver up to 5Gbps of downstream bandwidth and 1.2Gbps upstream. Operators that have deployed DOCSIS 3.1 headend gear and CPE have been turning on these OFDM and OFDM-A subcarriers in order to quickly improve bandwidth during the COVID-19 pandemic.
A blueprint for other MSOs
The node plus zero architecture notwithstanding, Mediacom’s approach to ultimately delivering 10G of bandwidth is a possible blueprint for other MSOs, particularly in the North American market. What Mediacom’s smart home demonstration shows clearly is that the tools that are available to operators now can deliver the speeds they will need to remain competitive through the end of the decade. The use of many of these tools is already underway.
Most operators are still providing return band of 5-42MHz. Using a mid-split design can push the upper limits of that band to 85MHz with a high split design giving operators up to 204MHz to work with in the return path. Some large operators have already started or completed their transition to mid-split, while others are jumping directly to a high-split architecture. At 204MHz, cable operators can offer 1Gbps of upstream bandwidth, which matches or exceeds what many telcos are offering through their FTTH networks.
But these upstream upgrades also require significant changes to the outside plant, including amplifiers and taps. For many cable operators, this isn’t necessarily a bad thing, as these critical outside plant components are nearing the end of their lifespan over the next five years, after having served in broadband networks for the last 10-20 years. Additionally, the replacement of these devices as part of mid-split and high-split architectures also help lay the groundwork for the eventual deployment of DOCSIS 4.0 and Extended Spectrum DOCSIS (ESD).
Though these upgrades put a lot on the plates of cable operators worldwide, the combination of all these transitions will ultimately lead to the complete overhaul and modernization of their broadband access networks, as they continue to migrate down the path towards 1.8GHz spectrum, Extended Spectrum or Full Duplex DOCSIS modulation, DAA, and virtualization. Again, all these changes will definitely occur in phases, as each operator weighs the vision of their future networks and services against the short- and long-term costs to get there.
But the end result of those efforts is exactly what Mediacom’s demonstration is intended to show: Cable operators with the capacity and capabilities in their networks to deliver customers advanced applications and services that go beyond what is available today.
Jeff Heynen is senior research director for broadband access and home networking at Dell'Oro Group. He joined Dell’Oro Group in 2018, and is responsible for the broadband access and home networking market research program. While at the firm, Heynen has expanded the broadband access and home networking coverage areas. Heynen’s research and analysis has been widely cited in leading trade and business publications. Heynen is a frequent speaker at industry conferences and events, including Broadband World Forum, CES, FoE Japan, FTTH Conference, and the SCTE Cable-Tec Expo. He can be reached at [email protected]; follow him @JeffHeynen.
Industry Voices are opinion columns written by outside contributors—often industry experts or analysts—who are invited to the conversation by FierceTelecom staff. They do not represent the opinions of FierceTelecom.