Getting Real About ‘Virtual’ CCAP

Just as cable starts to deploy a centralized, do-it-all next-generation access architecture, work is already underway to break it down, spread it out and begin to “virtualize” functions into software that have traditionally been hardwired.

Taking a lead role on this is R&D house CableLabs, which told Multichannel News it has kicked off a project that will investigate a virtual form of the Converged Cable Access Platform, a space-saving, high-density architecture that combines the functions of the cable-modem termination system and edge QAM (quadrature amplitude modulation), and puts all cable services under one roof, Chris Donley, director of SDN (software-defined networking) technology at CableLabs, said.

That vCCAP work, which Donley said is in the “relatively early” stages, stems from CableLabs’ study of the advantages promised by SDN and network functions virtualization (NFV) — two technology trends that have been gathering interest and momentum across the telecom industry.

In general terms, SDN separates the control plane from the data plane, while NFV aims to put into software functions that have been linked to purpose-built hardware, such as firewalls, Web filtering and load balancing, and instead operate them on generic servers. The belief is that a move toward SDN and NFV — and away from purpose- built hardware — will allow operators to accelerate the development and deployment of new services.

Donley said the CableLabs vCCAP project will focus on which elements of the architecture could be virtualized, with an initial goal to create a common architecture that still provides vendors with enough flexibly to differentiate their products. “My vision is to keep this as lightweight as possible to give a lot of room for innovation,” he said.

He said he expects the project team to produce a vCCAP technical report by the second half of the year. CableLabs and its members and partners will later determine whether new specs will be required to accommodate more CCAP virtualization.

Virtualization is a departure from the original vision for fully integrated CCAPs, which have generally taken the form of monolithic devices. Most CCAP suppliers said they have efforts underway to support virtualization, and don’t view it as disruptive to their product plans.

Virtualization is “absolutely in line with our roadmap,” Asaf Matatyaou, director of cable edge and access solutions at Harmonic, said.

Harmonic’s CCAP entry, the NSG Pro, is starting off as a dense edge QAM, with upstream components to be added later. Harmonic is also developing a more distributed form that will spread capacity deeper into the cable network. Matatyaou said routing is a leading candidate for virtualization. “Let the routers be routers, and let the CCAPs be CCAPs,” he said.

CommScope, whose CCAP is similar to Harmonic’s, has virtualization on its roadmap, a spokesman said.

Arris is also developing a virtualized CCAP that would complement its current CCAP-ready product, the E6000, a device that is starting off as a high-density CMTS that can support edge QAM via software upgrades. Arris hasn’t disclosed a timeline for a vCCAP.

Gainspeed, a startup, has not announced a product, but the company has acknowledged it is working on a virtual CCAP, adding that the approach, when linked to a more distributed allocation of capacity on the network, will be required if cable operators intend to scale up to deliver the capacities envisioned by DOCSIS 3.1 — up to 10 Gigabits per second downstream and 2 Gbps upstream.


Cable’s R&D consortium is investigating “virtualized” functions in a move that would speed new services to market.