As the cable industry moves closer to widespread deployment of video-on-demand, there's an increased need for a content-delivery platform that's both cost efficient for operators and receives Hollywood's quality blessing.
Cable's only pay-per-view network, In Demand, is working on such a scheme, and hopes to deploy it by early next year. Upstart TVN Entertainment Corp., which is testing a content-on-demand delivery system with Cablevision Systems Corp., also has its eye on this market.
Although a half-dozen local systems within Time Warner Cable, Charter Communications Inc., Comcast Corp. and Cox Communications Inc. have launched VOD via headend-based servers, the rest of the transmission system essentially relies on FedEx Corp. or United Parcel Service.
Movies are encoded in production houses, then shipped to servers across the country. But the efficiency of that model falls apart when hundreds of headends need hundreds of hours of content delivered each month.
TVN said its planned content-on-demand delivery system is a natural outgrowth of its near-VOD business. As the company's PPV business to C-band satellite dish owners started to dwindle several years ago, it launched a 40-channel NVOD service, competing with AT & T Broadband's Headend in the Sky.
Cablevision Systems Corp. and a handful of smaller MSOs signed up. Comcast, among others, also takes a few feeds that provide a different PPV programming mix than In Demand offers.
TVN's Dom Stasi, senior vice president, technology and business development, is starting work on the next step: Back-end delivery of VOD content that would encompass encoding and error-free satellite delivery to hundreds of headends across the U.S.
"We want to take advantage of the architecture," he said. "There are going to be pretty large memory banks at headends and nodes. Extraordinary economy can be achieved with all that memory, if we can send film assets as data."
VOD traffic flow is also unpredictable, which poses another design challenge.
"VOD essentially comes from the server," Stasi said. "It won't have a predictable relationship to its co-channels so you can't do statistical multiplexing."
Thus, operators need a content-on-demand delivery system that is as bandwidth-efficient as possible.
TVN already encodes movies for its NVOD service, but Stasi started encoding films on a scene-by-scene basis to see how low he could drive the data rate.
"We found that we could drive the data rate down to 3.2 megabits," he said. "That's a very low rate. And the studios, so far, are delightfully surprised at the quality."
It takes about eight hours for TVN to encode a movie for VOD. By driving it down to 3.2 megabits, the movie takes up less space on the server and an operator can serve more customers simultaneously, he said.
Stasi said a 3.2-megabit file at 8-to-1 compression allows an operator to handle eight simultaneous VOD users on a single analog channel. Today's more common 4.5 megabit files require a 4-to-1 to 5-to-1 compression rate, which means an operator could handle only four or five simultaneous users per analog channel.
Under TVN's plan, the company would encode movies, send them through its own server to a secure satellite-transmission facility, then uplink to a satellite for transmission to a headend server.
TVN owns a hybrid analog-digital online interactive-scheduling system (ADONISS) that tracks and maintains details of content sent through the system, Stasi said.
As movies are sent out, if there are any transmission errors, information flows back from individual headends to TVN. The company's software automatically corrects any problems, Stasi said.
"We aggregate error messages and will transmit data to only those places," he said. "The system automatically splices in packets where they belong."
The entire system is MPEG-2 and Ethernet-based, allowing TVN to interface with a variety of platforms, including cable and DSL providers.
By using 3.2-megabit files, TVN can also efficiently send more content. "We can send a whole month's worth of movies in a day," he said.
TVN is developing its pricing models. It's also working to get final approval from the studios for wide-scale deployment.
Jim Riley, senior vice president of business development, said TVN probably would structure its rates on a "per-gigabit-transport and management-fee basis."
In Demand is working on a similar satellite-distribution plan. It issued a request for proposals for a satellite-delivered VOD system this spring, and expects to launch in the first quarter of 2001, said John Vartanian, senior vice president, technology and operations.
"We'll be using our own transponder capacity," Vartanian said. "We'll be mixing and matching technology, to some extent."
In Demand plans to purchase a large file server-dubbed the "pitcher"-to store encoded movies. The films will be transmitted over In Demand's satellite transponders to a small caching device at the headend, Vartanian said.
The caching device takes a moment to determine if there are any transmission errors, corrects any faults, then sends the movie to the cable operator's VOD file server.
The "pitcher" will hold movies 30 to 45 days for transmission, Vartanian said.
In Demand is using a uniform 3.75-megabit coding specification agreed to by the Hollywood studios, Vartanian said. That includes 3.2 megabytes for video and 0.5 megabytes for data, such as the Dolby 5.1 stereo feed.
With transmission speeds of eight to nine megabytes, In Demand can send a two-hour movie in 45 to 50 minutes, Vartanian said. The caching device at the headend will store one or two movies-for just long enough to correct any errors-before sending them to the server, Vartanian said.
In Demand will bear the cost of the "pitcher" and license the asset-management system. Cable operators will likely absorb the approximately $20,000 cost for the caching device, he said.
In Demand counts AT & T Broadband, Time Warner Cable, Cox Communications Inc. and Comcast as owners. But TVN sees plenty of opportunity with the rest of the cable industry.
"Our first to market status gives us a very good advantage," Riley said. "We're the FedEx of the digital content business."