News / Infrastructure, Cloud & Telecom
DOCSIS 4.0 Extended to 3 GHz: Speeds of 25 Gbit/s on Existing HFC Networks Published on 28 September 2026 by Christ-loisele (2 min read)
CableLabs has published the technical specifications for an operational annex of DOCSIS 4.0, enabling the spectrum to be extended up to 3 GHz and achieving downstream speeds of 25 Gbit/s. This development aims to optimize HFC infrastructures without requiring major new investments.
A Spectral Extension to Double Performance
CableLabs has finalized the physical specifications for an operational annex of DOCSIS 4.0, extending the available bandwidth up to 3 GHz, compared to the initial 1.8 GHz. According to Light Reading , this update enables theoretical downstream speeds of 25 Gbit/s, nearly twice the 14 Gbit/s currently achieved under optimized conditions with DOCSIS 4.0. The new rules define requirements for nodes, Remote PHY equipment, and cable modems, leveraging 192 MHz OFDM channels for improved spectral efficiency.
This spectral extension demonstrates what the cable industry can achieve when operators, manufacturers, and experts collaborate to push the limits of existing networks.
Illustration: Lawing Tech Interoperability and Preparation for Higher Frequencies
The annex, published in September 2026 following collaboration between operators, manufacturers, and CableLabs, standardizes performance in terms of Total Composite Power (TCP) and Carrier-to-Composite Noise (CCN) , essential for ensuring compatibility between equipment. As CableLabs notes, this specification aims to facilitate deployment on existing HFC networks without additional infrastructure. Meanwhile, research is underway to explore an extension up to 6 GHz, though this remains exploratory according to Mark Bridges, the future CEO of CableLabs. Applied Optoelectronics Inc. is already working on a prototype amplifier to validate feasibility at 3 GHz.
What This Means Here
For African operators using HFC infrastructures, such as those in Benin or other West African countries, this advancement could significantly increase network capacity without heavy investments in additional fiber optics. The increased speeds could support the growing demand for bandwidth for cloud services, high-definition video, and professional applications, while reducing operational costs. However, adoption will depend on the availability of compatible equipment and the ability of local operators to integrate these specifications into their existing networks.
Next Steps and Industry Collaboration
Discussions on deployment strategies and operational readiness will take center stage at the DOCSIS 4.0 Meetup during the upcoming SCTE TechExpo26, scheduled for September 2026 in Atlanta. This initiative underscores the importance of cooperation among industry players to innovate without fragmenting the ecosystem, as highlighted by CableLabs engineers Ricardo Villa and Karthik Sundaresan. Their analysis has helped determine current technical limits and guide future developments.
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