jchapmanBy John Chapman, Cisco Fellow, CTO, Cable Access BU

This week, we and 10,000 or so hard-core engineering colleagues within the cable industry descend upon the city once known as the cable capital of the world — Denver, Colorado — and, like it’s been since the earliest days of the Society of Cable Telecommunications Engineers’ annual Cable-Tec Expo, a trending topic, now and forever, is bandwidth.

The reasons why are obvious, but indulge me a brief recap: Consumer usage of broadband grows at an compound annual rate of 50% or more, ever since about 2009, when Netflix began streaming video, in addition to mailing DVDs. Add to that the sheer number of video-capable, IP-connected screens we all use, and the fact that video itself is only scheduled to get bigger (we’re looking at you 4K), and it’s easy to envision why it’s a considerable challenge to keep the cable infrastructure updated, and capable of ever-increasing carrying capacities.

Here in Denver, we are focused on this challenge. Big picture, we are “transforming” cable access from a DOCSIS focus, to integrate DOCSIS with service provider  WiFi, PON & FTTx, and MetroE into a single, easily- managed portfolio, which only Cisco can deliver. Doubleclicking on the DOCSIS pillar alone, we are taking the CMTS architecture and redefining it to deliver far more bandwidth, for far less cost. We see two technologies that stand out:

  1. CCAP (Converged Cable Access Platform): Officially CCAP takes  the unintentionally-but-nonetheless disparate QAM modulators associated with the video, voice and data service lines offered by cable operators, and integrates them; Unofficially, CCAP is short-hand for a far-denser CMTS, which delivers far more bandwidth in less space, using less power, more efficiently
  2. Remote PHY: This technology separates the physical (PHY) and Mac elements of DOCSIS-based gear. PHY elements can then be pushed out into distributed hubs and “fiber-deep” HFC nodes. Distributing DOCSIS PHYs in this way extends cost-effective Ethernet networks to the neighborhood, and reduces the space and power required in headends and distributed hubs. Reducing the distance between subscriber and PHY enables the DOCSIS 3.1 Gigasphere to achieve maximum bandwidths.

Though these technologies have been developed separately, we think that if the end game is to increase bandwidth to multi-Gigabit speeds without increasing operational expenditures, then the answer is to combine CCAP and remote PHY. More specifically, to centralize the sophisticated DOCSIS functions into fewer, but powerful nodes in easily-managed locations, which control simple “dumb” remote PHYs distributed to hubs and nodes through the network.

Cable operators like this because it saves up to 60% in rack space, and 40% in power consumption at participating hub locations, and it can lead to the scale and speed they need to move new products and services to market faster. Engineers especially like it because it lowers any worry levels associated with the need to stay ahead of the hockey-stick growth in broadband demand. No longer does 50% per year bandwidth growth mean accelerating needs for hub space and power.

And that brings us right back to the “big picture”: Delivering a “one network” strategy for residential and commercial services. Going big on capacity means utilizing CCAP and remote PHY. Going bigger, which will be the next big chapter in broadband infrastructure, is moving to PON, MetroE, Software Defined Network (SDN) and Network Function Virtualization (NFV). Deploying this CCAP core + remote PHY architecture is key to these bigger picture transitions. Remote PHY nodes also offer the opportunity to integrate PON capabilities, enabling node-by-node evolution to PON, reducing the investment required to make the PON transition. And with the PHY layer removed, CCAP cores can be virtual, as well as physical. SDN allows us to manage all of these access components in a unified manner.

Come by Cisco’s booth #1460 this week and let us show it to you. If capacity is your bailiwick, we have the goods you need to see. In addition – check out this video, the latest installment of Cisco’s Video SPotlight series, where Todd McCrum, senior director of Business Devlopment for Cisco’s Cable Access business, discusses second-generation CCAP solutions. He looks beyond mere convergence, toward advanced services down the road.

With everything moving towards cloud and virtualization, Todd notes that remote distributed architecture is merely a first step in Cisco’s five pillar CCAP strategy, which includes remote PHY, NFV support, and a significant investment in SDN technology. As Todd states, CCAP and DOCSIS 3.1 will “table stakes” for all players involved in cable access but Cisco is leading the way with the launch of CBR-8.


Tweet us @CiscoSPVideo if you have any questions about our demos.


David Yates

as Director of Service Provider Video Marketing at Cisco