Options for Extending DOCSIS Capabilities

As the Internet of Things puts more connected devices in the home – and as video streaming, virtual reality and future applications demand gigabit-plus bandwidth -- cable operators are evaluating new ..

tom cloonan

Tom Cloonan, CTO Network Solutions

As the Internet of Things puts more connected devices in the home – and as video streaming, virtual reality and future applications demand gigabit-plus bandwidth -- cable operators are evaluating new technologies to deliver more capacity to end-users. Estimates point to the need to bring 20 Gbps into the home within the next 10 to 15 years.

Cable operators are already embracing the advantages of DOCSIS technology, but the conversations at this year’s SCTE Cable-Tec Expo will shift toward research that is being done to extend DOCSIS to provide even more future value.

Multiple research projects are being conducted by cable operators and industry vendors to evaluate DOCSIS approaches, but the two main opportunities focus on Full Spectrum DOCSIS (FDX) and Ultra-High-Split + Extended Spectrum DOCSIS. Also, some operators may choose to work with both options through a phased approach or even simultaneously.

US Avg BW per SubscriberFull Spectrum DOCSIS (FDX)

Cable operators looking to maximize their upstream and downstream bandwidth capacities without sacrificing downstream spectrum may opt for FDX. They will need to be able to move quickly to the Node+0 environment and be willing to upgrade their CMTSs, Nodes, and CMs. However, there is also research being conducted to determine whether the performance of FDX amplifiers could permit Node+X FDX operation and this solution might also require upgrades to Actives. As subscriber bandwidth demands grow and equipment capacities increase, operators will need to expand their upstream spectrum. FDX offers a valuable technique to do so.

Ultra-High-Split + Extended Spectrum DOCSIS

This approach may be better suited for cable operators that want assurances that their future high-capacity networks will work in existing Node+X environments that may or may not be supported by FDX operation. They are looking to continue their current approaches to expand upstream and downstream bandwidth capacities using Frequency Division Duplex (FDD) techniques that maintain a simple guard-band separation between the upstream and downstream spectrum. They are also willing to sacrifice some downstream to increase upstream spectrum. As bandwidth demands grow and equipment capacities increase, they will need to upgrade their CMTSs, Nodes and Actives, and CMs to support the new upstream split and downstream extended spectrum.

At ARRIS, we’re conducting research to explore these approaches further to extend DOCSIS to address future consumer bandwidth needs. We look forward to working alongside our customers to evolve their networks to deliver the solutions they will need well into the future.