At the latest DOCSIS 4.0 Interop·Labs event, a record number of modem suppliers were on hand to delve deep into upstream speed and other aspects of the DOCSIS 4.0 specifications. We want to thank the participants who helped make the event successful and once again helped us achieve a high level of productivity.

We cannot highlight enough how CableLabs provides a neutral testing ground for suppliers and operators to come together and showcase compatibility across interfaces defined in our DOCSIS 4.0 specifications. The gathering of suppliers and products in one location is extremely valuable to the participants to see how the technology is being implemented across multiple platforms. The DOCSIS 4.0 specifications are proscriptive, yet there’s plenty of room for innovation to differentiate products and offerings.

Combining interoperability events for these technologies drives home the fact that compatibility across all system components is a high priority for the industry.

To recap:

• Everything is coming up gigabits!
• Downstream speeds faster than 9 Gbps through a DOCSIS 4.0 modem are the new normal, limited only by the availability of a single 10 Gbps interface on the modems.
• Upstream speeds now exceed 2 Gbps on DOCSIS 4.0 modems and can go higher.
• We continue to examine the copious data available from the modems — in particular, DOCSIS 4.0 cable modem Proactive Network Maintenance (PNM) functions.
• DOCSIS 4.0 security technologies are coming along nicely, and their recent availability showcases the advancing maturity of the products.

DOCSIS 4.0 technology is putting down a marker. These products are delivering on the promise of multi-gigabit speeds that will benefit consumers around the world. Among suppliers and operators in our labs, we’re seeing unprecedented passion for interoperability, for unrivaled speeds and for getting these products to market.

Record Supplier Participation

Attendance at the interop was high, including new suppliers and products. Three operators joined us to observe demonstrations, interact with the suppliers and talk about their own DOCSIS 4.0 network progress.

Among the suppliers were CommScope and Harmonic, which brought DOCSIS 4.0 cores to the interop. For the first time, we saw three 1.8 GHz Remote PHY Devices (RPDs) from separate suppliers including CommScope, Harmonic and Vecima Networks. Also, for the first time, eight DOCSIS 4.0 modem suppliers — Arcadyan, Askey, Gemtek, Hitron Technologies, Sagemcom, Sercomm, Ubee Interactive and Vantiva — brought multiple cable modem models. Microchip Technology participated with its clock and timing system. The availability of record numbers of both DOCSIS 4.0 RPDs and DOCSIS 4.0 cable modems shows that products continue to proliferate as these suppliers prepare for SCTE TechExpo 2024 later this month.

Testing scenarios involved using a virtual core from one supplier, and RPDs and DOCSIS 4.0 cable modems from various other suppliers. The products were mixed and matched to verify interoperability scenarios and speeds through the system. As before, DOCSIS 3.1 and DOCSIS 4.0 devices were combined to demonstrate the cross-compatibility of existing and new technology. Suppliers providing test equipment used these setups to verify their solutions.

Sustained Speed

Achieving a rate of 9 Gbps (or faster) downstream through a DOCSIS 4.0 cable modem is now the new normal. Multigigabit speed is a core pillar of the 10G platform. At this interop, all modems achieved that downstream rate of speed — testament to the work achieved at previous interops.

At the August interop, we looked at upstream speed — that is, the stability of very high-speed traffic on upstream channels. Using a DOCSIS 4.0 ultra-high split, the modems in attendance consistently achieved more than 2 Gbps upstream. Upstream is trickier than the downstream: Whereas downstream is a continuous broadcast from one transmitter (the RPD), upstream is bursty, consisting of multiple modems contributing to the orthogonal frequency-division multiple access (OFDMA) signals that the RPD has to “catch” and accurately demodulate. That upstream burst receiver in the RPD is arguably the most complicated component of the system, especially considering the data rates in play.

So, we’ve arrived at a point where a DOCSIS 4.0 modem is pairing download speeds faster than 9 Gbps with upload speeds faster than 2 Gbps (and with the capability to go even faster). And we’re talking about a single modem. The service group can achieve even more capacity and speed, which means individual modems can also go higher.

Additional DOCSIS 4.0 Cable Modem Operations

Beyond speed, three other aspects of DOCSIS 4.0 technology stood out, offering a look at the maturity of the products at the interop.

PNM

PNM is an important function for cable modems. It’s a proven tool that engineers and technicians use for maintenance, troubleshooting and improvement of the cable plant. More and more, the signals on the plant are OFDM and OFDMA, which provide higher speeds and capacities than traditional quadrature amplitude modulation (QAM) signals.

At this event, we looked at five PNM tests that were run on all the modems. And because DOCSIS 4.0 modems generate more OFDM and OFDMA signals, more data is available. This is a sign of product maturity, responding to these data requests. And the modems have this down. This PNM data will enable the most efficient operation of the coaxial cable network, keeping the data levels at their peak by using the more efficient OFDM and OFDMA signals.

Security

Cable broadband is widely deployed. Hundreds of millions of consumers use DOCSIS technology every day as they live, work, learn and play. DOCSIS 4.0 technology includes strengthened measures to meet the threats that come with online activity. Suffice it to say, new security features are now appearing in products in the labs, and they’re being tested for both functionality and interoperability.

Remote PHY Interoperability

Although modems were the focus, the event also looked at the interoperability between DOCSIS 4.0 cores and RPDs. We branched into more and different configurations, moving beyond “one size fits all” configurations. These products are going to be deployed in many scenarios, and going deeper into these various configurations will ensure flexibility as DOCSIS 4.0 technology moves into the field.

Join Us Next Time

The next DOCSIS 4.0 interop is planned for the week of Nov. 4 at CableLabs’ headquarters in Louisville, Colorado. The event will provide an opportunity for both new suppliers and new products as we all prepare for the new calendar year.

Right around the corner in March 2025 are CableLabs Winter Conference and Smaller Market Conference.