Comcast’s Unsung Hero: The Network

Newfound operational efficiencies were on full display last week when Comcast posted the results of a solid fourth quarter. In addition to halting years of video subscriber losses, the MSO trimmed truck rolls by 3.5 million as as self-installs accounted for 42% of total installs in 2013 and more than a third of customers managed their accounts online.

On top of that, Comcast has sped up its ability to develop and launch new products. Its IP-capable X1 video platform is now available in all Comcast systems and, last fall, the operator launched an electronic sellthrough service that lets customers buy and rent movies and TV shows, forging a weapon it can use against Apple iTunes, Amazon Instant Video, Vudu and other over-the-top services encroaching on cable’s video turf.

Although it takes a commitment from the top down to achieve these operational efficiency gains while accelerating the company’s ability to boot up new offerings, the unsung hero may be the network that ties everything together — from an optical core network that connects all of Comcast’s systems to a speedy data superhighway, to an expanding private cloud that feeds a growing library of on-demand video to set-tops and other devices.

“We’ve gone from a company that specified and acquired end-to-end solutions to one that’s looking at the architecture for cost-effective scale, product differentiation and platforms,” John Schanz, executive vice president and chief network officer for Comcast Cable, said.

Comcast has poured significant dollars and manpower into that network-focused vision and, based on the latest results, those investments appear to be paying off.

But that job and those investments never really end. To keep the engine that drives the business in tip-top condition, it must always be fed and fine-tuned.

Schanz said his top priority in 2014 is “to continue investing in operational excellence … [and] to keep the network operating at peak performance.” A close second is a commitment to building “platforms that are extensible and help create product differentiation.”

Key to that effort is one of Comcast’s biggest platforms — the optical core network that carries the MSO’s voice, video and Internet traffic for residential and business customers. Over the years, that core network has been strengthened and expanded to help Comcast stay ahead of the pace.


Comcast started with a 10-Gigabit core network, upgraded to 40 Gb, and then jumped to 100 Gb, which is predominantly where the MSO’s core network is today. But Comcast is getting ready to step up to the next rung on that ladder — 1 Terabit-per-second wavelengths.

Early evidence of that work emerged last fall, when Comcast and tech partner Ciena announced the completion of a live field trial of a 1-Terabit optical transmission covering nearly 1,000 kilometers that connected Ashburn, Va., to Charlotte, N.C. Comcast and Ciena said it was the first trial in which live data traffic was fed over a 1-Terabit 16-QAM “super-channel” on the legacy commercial network.

“It wasn’t in a lab,” Schantz explained. “It was on a real, live production network.”

And 1 Terabit could gradually become the capacity standard on that core. “I suspect that we will begin to deploy terabit wavelengths toward the end of this year, but only surgically where we need them,” he said, predicting that Comcast could have 1-Terabit links “widely deployed” by sometime in 2015.


As a keynoter at the International CES six years ago, Comcast chairman and CEO Brian Roberts announced “Project Infinity,” an initiative aimed at expanding the operator’s video-on-demand library. At the time, the plan called for Comcast to offer more than 1,000 HD VOD “choices” by the end of 2008. When the project was launched, Comcast offered a VOD library of about 10,000 titles, but just 250 in HD.

Roberts didn’t outline the technical underpinnings of Project Infi nity, but a big driver behind it was the development of a video-optimized private cloud that the operator calls the Comcast Content Delivery Network (CCDN).

The CCDN has expanded and evolved over the years in terms of both content and supported devices. It began as a VOD platform for native set-top boxes, but today it also bridges content to a growing array of IP-connected devices, including PCs, smartphones, tablets and gaming consoles such as Microsoft’s Xbox 360.

On the content end, the CCDN now provides the basis for a set-top VOD library of 50,000 “choices,” and more than 300,000 choices through the website.

Expect that library to continue to expand as the cloud driving it evolves. The CCDN today uses a centralized location for content ingest (plus a second for redundancy), which feeds a handful of hubs. The hubs contain the digital library servers that stores all of the movies and TV shows that, in turn, send a portion of that library to caching gateways that cache the most popular content. VOD pumps, also installed at the edge, stream content to set-tops and other devices.

By putting the oft-used titles closer to the customer, this hierarchical approach, used in all CDNs, provides efficiency and cuts down on transport costs.

And what’s considered the edge of the CCDN will likely extend deeper into the network and in many more locations, Schanz said, adding, “The architecture is scaling towards a richer edge facing the customer.”


From an optical core network to an expanding private cloud, Comcast’s technology backbone may be the real hero behind its 4Q results.