Virtualized broadband equipment supplier Harmonic said today that Charter will use the Harmonic virtualized cable modem termination system (vCMTS) to support the cable company’s DOCSIS 3.1, DOCSIS 4.0 and distributed access architecture (DAA) plans – which are all part of the cable company’s plans for network-wide multi-gigabit service with symmetrical gigabit speeds.
Although today’s release didn’t specify deployment dates and a Harmonic spokesperson declined to provide additional information at this time, Charter President of Product and Technology Rich DiGeronimo said in December that Charter plans to deploy vCMTSs in 2024.
Virtualized CMTSs are a key element of distributed access architecture (DAA) and both are designed to enable cablecos’ existing hybrid fiber coax (HFC) infrastructure to support higher speeds with either today’s DOCSIS 3.1 cable modem technology or DOCSIS 4.0, the next generation of that technology.
As DiGeronimo explained in December, the vCMTS replaces the traditional hardware-based CMTS traditionally deployed in a network hub. Instead, the functionality is virtualized and distributed via network nodes located closer to customer locations. Radio frequency generation is also moved to the hub with DAA.
Three-Phase Plans
Charter expects to introduce DAA and vCMTS in 2024 in the second phase of the company’s three-step plans to upgrade its entire network by 2025.
The first phase of the three-step plan, currently underway, involves upgrading 15% of Charter’s territory to support speeds of up to 2 Gbps downstream and 1 Gbps upstream. Phase two reaches an additional 50% of the company’s territory, bringing speeds up to 5 Gbps downstream and 1 Gbps upstream. The final 35% of the company’s territory, targeted for speeds of 10/1 Gbps, will be upgraded in phase three.
Phase Two: vCMTSs Arrive
In addition to deploying DAA and vCMTSs in the second phase, Charter plans to deploy DOCSIS 4.0 modems at the customer premises and to deploy DOCSIS 3.1 remotePHY device (RPD) modules, as well as 10G Ethernet and remote optical line terminal (OLT) capability, at the node. OLT functionality would be implemented via modules that can support fiber broadband, which the company envisions deploying in some areas of its existing footprint.
Areas targeted for the second phase also would receive upgrades that the initial 15% of Charter’s territory will receive in the first phase. Those plans include upgrading amplifiers to support 1.2 GHz of spectrum within the coax portion of the connection and implementing high splits, which dedicate a larger portion of total spectrum to the upstream connection.
Phase Three: “Fully Deploying DOCSIS 4.0”
As DiGeronimo explained in December, the third phase of Charter’s network upgrade plans will get underway in late 2024 and will involve “fully deploying next-generation DOCSIS 4.0 technology” by doing the same upgrades as for phase two but using a new DOCSIS 4.0 RPD module in the node and upgrading amplifiers to increase the spectrum available within the coax portion of the link to 1.8 GHz.
Harmonic vCMTSs apparently will be part of those deployments as well, as the Harmonic press release notes that the systems will support both DOCSIS 3.1 and DOCSIS 4.0 for Charter.
Although Harmonic offers RPDs, the company’s web page notes that its vCMTS is “agnostic” to the RPD.
