The path to DOCSIS 4.0 networks is built on a series of important milestones, and one of the first is now being achieved across the industry. As part of the CableLabs DOCSIS Certification program, cable modem devices from GemTek, Hitron, MaxLinear, Sagemcom, Sercomm and Ubee have successfully reached DOCSIS 3.1 Verified for Interoperability (VFI) status. The certified devices span chipsets from both Broadcom and MaxLinear. This milestone marks an important step in validating interoperability on DOCSIS 3.1 networks and laying the groundwork for next-generation DOCSIS 4.0 deployments.
DOCSIS 3.1 VFI represents the initial phase of the DOCSIS 4.0 certification journey. At this stage, devices are verified in the CableLabs lab to ensure they interoperate reliably within a multi-vendor DOCSIS 3.1 environment. This process serves as a critical checkpoint: before advancing to full DOCSIS 4.0 certification, devices must first demonstrate stable, standards-based operation in today’s deployed networks.
Advancing Network Evolution Through Industry Collaboration
CableLabs plays a central role by providing a neutral, rigorous validation environment where interoperability is tested across implementations. Our interoperability events help device manufacturers mature their products by providing an opportunity to work with a multitude of vendors. The CableLabs Certification program ultimately verifies conformance to the specifications and ability to work in any cable operator network. By bringing together equipment from multiple vendors and validating real-world behavior, the program helps ensure that operators can deploy new solutions with confidence — knowing they will function as expected in diverse network environments.
This progress aligns closely with the CableLabs Technology Vision for Network Evolution, which outlines how the industry is transitioning toward more flexible, scalable and high-performance broadband architectures. Enabling seamless interoperability across technologies and vendors is foundational to this evolution, allowing operators to adapt their networks to meet growing demands.
The VFI milestone is a tangible example of that vision in action, helping bridge today’s DOCSIS 3.1 deployments with tomorrow’s DOCSIS 4.0 capabilities.
Next Stop: Full DOCSIS 4.0 Certification
Importantly, this effort spans devices covering the full range of DOCSIS 4.0 technologies, including both Frequency Division Duplex (FDD) and Full Duplex (FDX) modes of operations. Establishing interoperability early through VFI creates a common foundation across these deployment models, helping reduce complexity as operators evolve their networks.
The vendors achieving DOCSIS 3.1 VFI status represent a meaningful industry accomplishment. While each has contributed through its own development and testing efforts, the broader success lies in demonstrating that multi-vendor interoperability is not only achievable, but repeatable. This is essential to maintaining the flexibility and choice that operators depend on.
It’s important to note that VFI is just the beginning. Devices that have achieved this milestone will continue through the DOCSIS 4.0 certification process, where more comprehensive testing will validate full compliance with the suite of DOCSIS 4.0 specifications.
As the industry moves forward, milestones like DOCSIS 3.1 VFI status highlight the value of collaboration, open standards and independent validation. Together, these efforts are helping ensure a smooth and reliable transition to DOCSIS 4.0 networks — benefiting operators, vendors and ultimately the customers who rely on high-performance broadband services.
Stay tuned for more DOCSIS 4.0 technology updates and upcoming Interop·Labs events.
