Combined DOCSIS 4.0 Interop Event Stresses Network Interoperability and Virtualization 

DOCSIS 4.0 Ecosystem Interoperability

Doug Jones
Principal Architect

Feb 27, 2024

Key Points

  • The recent Interop•Labs event combined systems and components to demonstrate multi-supplier interoperability across the DOCSIS 4.0 ecosystem.
  • Test scenarios included combining DOCSIS 3.1 and DOCSIS 4.0 equipment to demonstrate additional flexibility for operators.
  • Interoperability is key to creating a healthier ecosystem because it enables more competition and operator scalability.

CableLabs and Kyrio hosted a combined DOCSIS® 4.0 technology and Distributed Access Architecture (DAA) Interop•Labs event February 12–15 at our headquarters in Louisville, Colorado. This was the first combined interop between CableLabs and its subsidiary, and the involved suppliers and operators made it a success.

At this Interop•Labs event, the exercises included both DOCSIS 4.0 cable modems and Remote PHY equipment, including virtualized cores and Remote PHY Devices (RPDs) that support DOCSIS 4.0 technology. During the week, mixing and matching of systems and components demonstrated multi-supplier interoperability across the DOCSIS 4.0 ecosystem.

Interop Takeaways

Casa Systems, CommScope and Harmonic brought DOCSIS 4.0 cores to the interop, and Casa Systems, Cisco, CommScope, DCT-DELTA, Harmonic, Teleste and Vecima brought RPDs that offered a mix of DOCSIS 3.1 and DOCSIS 4.0 technologies. Arcadyan, MaxLinear and Ubee Interactive showcased DOCSIS 4.0 modems. Rohde & Schwarz also participated with its DOCSIS 4.0 test and measurement system. Operators attended to observe the interop, interact with the suppliers and talk about their DOCSIS 4.0 technology plans.

The focus of the interop was interoperability across the ecosystem. A common test scenario at the event involved a virtual core from supplier A, an RPD from supplier B and a DOCSIS 4.0 modem from supplier C, all connected and operating according to specifications. The products were mixed and matched to investigate interoperability scenarios, with suppliers pitching in to analyze the results. To demonstrate extra flexibility for cable operators, suppliers mixed DOCSIS 3.1 and DOCSIS 4.0 equipment because the specifications are written for cross-compatibility.

DOCSIS Interop Labs

Above, engineers collaborate during the first combined DOCSIS 4.0 Interop•Labs event hosted by CableLabs and its subsidiary, Kyrio.

Interestingly, the interop illustrated how the traditional cable modem termination system (CMTS) has been disrupted by virtualization. Provided by one supplier, the CMTS used to be one box that did it all. Now, the software components have been abstracted into a virtual core that runs on servers in our data center, while the physical-layer components have migrated to the fiber node. This virtual architecture provides both better scalability and improved flexibility for the software, as well as better physical-layer performance on the coaxial cable. And in between, the fiber-optic cable uses much more scalable digital Ethernet connections.

The interop also demonstrated that the core and fiber node components can come from different suppliers because that interface is described in the CableLabs Remote PHY specifications. Looking at interoperability from all angles benefits all stakeholders. Interoperability enables a larger market in which suppliers can compete, which leads to varying competitive strategies and healthier ecosystems. Interoperability gives operators the confidence to plan large installations and the certainty that the equipment they put in the field this year will work for years to come.

Remote PHY interoperability events began in 2017 with DOCSIS 3.1 technology, so these solutions have been in the field for years and have matured. This interop shows that the migration to DOCSIS 4.0 technology is both very far along and proceeding smoothly — and that the supplier community has embraced interoperability among system components.

It's About Network Cohesion

The integration and optimization of the DOCSIS 4.0 ecosystem is underway. The goal has moved beyond simply booting DOCSIS 4.0 modems. Rather, we’re putting together all the parts, mixing and matching from different suppliers, demonstrating interoperability across the interfaces defined in CableLabs specification and achieving the multi-gigabit speeds and other advanced capabilities of DOCSIS 4.0 technology such as security, low latency and proactive network maintenance.

Other parts of the DOCSIS 4.0 ecosystem are also becoming available, including hybrid fiber coax (HFC) network equipment such as amplifiers, taps and passives.

To learn more about this exciting evolution, join us next month at CableLabs Winter Conference. This exclusive event for CableLabs members and the NDA vendor community will explore DOCSIS technology in two powerful sessions: “Unleashing the Full Potential of the DOCSIS 4.0 Network” and “A Vendor Perspective on DOCSIS 4.0 Technology Implementation.” You’ll hear from industry leaders about effective strategies, opportunities and benefits of the DOCSIS 4.0 network. Join us!