Harmonic has a blueprint for multi-gig MDUs

Harmonic thinks it has the solution to a common problem for operators: how to get fiber and upgraded cable services to apartment buildings and other old facilities with legacy wiring.

The challenge these operators face is bringing high-speed broadband to customers in multi-dwelling units (MDU) with minimal disruption to their homes — "for two reasons: One, it's a hassle for tenants. Two, it's incredibly expensive to rewire a building,” said Dan Gledhill, who heads Harmonic's broadband business.

Harmonic is solving this problem by combining its cOS (formerly CableOS) software and “Oyster node” that can be used as both a Remote PHY Device (RPD) or an Optical Line Terminal (OLT). That means operators can either use existing coax wiring to deliver DOCSIS 3.1 services directly from the node, similarly to how single-family homes receive DOCSIS services. Or, they can pull fiber to the node and deliver 10G EPON or XGS-PON.

The Oyster node can be used when there is already fiber to every room or unit in a building, (Gledhill called this “the simplest scenario"), and the node sits in the basement of a building to serve fiber-to-the-home internet subscribers from there.

The second use case is where a building does not have fiber to each room, but only to the premise or the curb, with coax to each unit. Gledhill said this represents “a very large percentage” of the MDU and hospitality footprint. And interestingly, the Harmonic solution for that scenario is the same as when there is fiber in every room.

The Oyster node (which is about the size of two tissue boxes) can also enable 8.5 gigabit broadband through Harmonic’s BoostD 3.1 DOCSIS technology. To get full spectrum DOCSIS 3.1, Harmonic takes existing spectrum and adds more Orthogonal Frequency Division Multiplexing (OFDM), a technique used to transmit large amounts of digital data over a radio wave. According to Gledhill, every node Harmonic has deployed since 2017 is capable of BoostD 3.1 DOCSIS to get to 8.5-gig speeds.

Harmonic versus MoCA, G.hn

There are some key differences between the Harmonic MDU strategy and others, like Multimedia over Coax Alliance (MoCA) and "Gigabit Home Network"  (G.hn).

G.hn refers to a high-speed broadband network infrastructure designed to deliver gigabit (or higher) internet speeds to residences within multi-unit buildings. Meanwhile, MoCA allows operators to use coaxial cables in a building to create a network for devices like computers, gaming consoles, smart TVs and streaming devices.

Unlike G.hn and MoCA, Harmonic’s Oyster node can parse out different service tiers for each unit in an MDU. “Every customer can get their own package, and we can actually sort of shape the traffic so that the customer gets what they pay for,” Gledhill said.

Dell’Oro Group’s Jeff Heynen noted other solutions on the market, including Nokia’s, *Positron Access and InCoax, require operators to deploy fiber to the building, then use MoCA for the in-building connections over coax to each resident. 

With both Harmonic’s toolset and MoCA, the idea is to limit the disruption of building owners and residents by re-using the existing coax wiring.

However, another key difference is that special equipment is needed at both the main node of the MDU and in each individual home to support MoCA technology. That assumes that the internet provider has fiber optic cables connected to the building, or will install them, but Heynen said this may not always be the case. With the Harmonic solution, the cable operator isn’t required to deploy any new fiber and can instead use the Oyster as an RPD, turning the building into any number of service groups.

“Even more important is that the [Harmonic] solution doesn’t require any swap out of existing DOCSIS CPE, resulting in even less disruption for the building owner and residents,” he added.

The Harmonic cOS platform can also manage both FTTH and DOCSIS, giving operators “a lot of flexibility in how they address MDUs, SFU residential and even business customers.” If the equipment at the customer's end, like modems or optical network terminals (ONTs), can be managed in the same way, then providers can set up their services more quickly and troubleshoot them in a similar manner if problems arise.

An ‘operator-agnostic’ solution

As operators expand and grow average revenue per user (ARPU) across their footprints, MDUs are an important segment, Omdia analyst Jaimie Lenderman told Fierce Telecom.

Particularly in the U.S., a large percentage of MDUs are wired for coax-based services, according to Lenderman. As operators try to meet increasing demand for higher bandwidth and new services, a full fiber retrofit “is not always a viable solution,” she said, and products like Harmonic’s MDU solution create options for operators looking to expand or continue to service these facilities with minimal disturbance to tenants.

The essence of this type of solution is that it is “operator type-agnostic,” added Lenderman. “As long as there is a fiber-based PON network in the footprint, an operator can support the coax-based MDUs segment of the market.”

*** Editor's note 2/20/24: Positron reached out after this article was published with some clarifications about its G.hn access solution for MDUs. CTO Pierre Trudeau told Fierce that its G.hn Access Multiplier (GAM) product actually can parse out different service tiers for each customer in an MDU building.

Additionally, while some implementations of G.hn may differ, he said new fiber doesn't necessarily need to be deployed in MDU scenarios using Positron's G.hn product. GAM can tap into fiber at the curb via an ONT and extend gigabit speeds to existing telephone cables or coax inside of a building. Where there is no fiber to the curb, the company uses fixed wireless access radios. Unlike DOCSIS, G.hn controls the bandwidth allocation to optimize the 2-200 MHz of spectrum usage between the upstream and downstream direction, according to Trudeau.