Comcast Takes VOD to ‘Infinity’

First Phase of Content-Distribution Buildout Wraps In Philadelphia, D.C. Regions

By Todd Spangler -- Multichannel News, 8/9/2010 12:01:00 AM

The road to infinity is paved with fiber-optic cable — and gigantic server farms.

Comcast has completed the first phase of the “Project Infinity” video-on-demand content- distribution network for its Washington, D.C., and Philadelphia regions. The MSO claims it has put the infrastructure in place to serve a virtually unlimited amount of VOD.

“We are focused on offering an infinite amount of choice,” said Mark Muehl, Comcast senior vice president of product engineering.

With the initial upgrade, being marketed under Comcast’s broader Xfinity brand, the operator has boosted on-demand capacity from 8,500 hours to about 70,000 hours. In D.C. and Philly, Comcast had added 9,000 new movie titles per month, offering a total of 25,000 free and transactional titles.

That expansion is possible thanks to what the MSO calls the Comcast Content Distribution Network, or CCDN. In this architecture, popular content is cached at the “edge,” while less-frequently accessed titles are delivered as MPEG-2 streams directly out of a centralized library to subscribers over Comcast’s fiber-optic backbone network (see “Comcast Preps for VOD ‘Infinity,’ ” March 30, 2009, page 3). The CCDN means that libraries do not need to be distributed in their entirety to Comcast’s 100-plus distribution points, simplifying management and reducing storage costs.

Comcast has built out the Project Infinity VOD system with vendors including Cisco Systems, Muehl said. The operator has developed proprietary caching algorithms to find the optimal balance between storage at the edge versus the core. “If you have 100 requests, you want as small a percentage as possible of those served from the central library,” he said.

Today, the operator has two central libraries in place serving East Coast regions, and it is in the process of adding two more in other parts of the country. Ultimately, those four centers will connect those more than 100 “islands” of local VOD servers, located in Comcast headends and facilities across the U.S.

“We want a cookie-cutter design, so we get predictable performance,” he said.

Citing “security reasons,” Muehl declined to identify the locations of the VOD centers. Previously, two locations Comcast was considering were West Chester, Pa., and Denver, sources have said.

Muehl also declined to provide details on usage statistics, such as the average number of streams served centrally. He noted, though, that subscribers access literally everything in the expanded VOD library at least once per week.

Comcast CEO Brian Roberts first described Project Infinity in a keynote at the 2008 Consumer Electronics Show. At the time, he described a strategy in which Comcast would provide not only a massive amount of content via VOD but also online.

Currently, the CCDN doesn’t deliver content for Comcast’s “TV Everywhere” service, Fancast Xfinity, which lets cable-TV subscribers watch about 1,500 movies on the Web. The goal is to eventually combine the infrastructure that serves VOD and Internet video, Muehl said.

“Over time, we see these technologies coming together,” he said.

In addition, CCDN could be adapted for time-shifting services, such as network-based digital video recording. “We haven’t announced network DVR plans, but we could leverage the CCDN to deliver that,” Muehl said.