Cable ops are beginning to enjoy success with video-on-demand (VOD), but they face significant obstacles. To support a maturing business—and to turn less easily accessible potential revenue streams into real profits—both the architectures and software driving them will need far more sophistication. These changes must be implemented as demand grows and programming evolves. And growth is occurring on many levels. On the programming side, there are more movies available and more types of services (including subscription VOD and on-demand events). Demand is greater as well: VOD footprints, and buy-rates within those footprints, both are on the rise. After the truck-chasers In the overview, VOD is entering a phase similar to what high-speed data experienced in the late 1990s: After an initial “truck-chaser” period in which simply offering services—no matter how rudimentary—guaranteed success, operators needed to offer more reliable and differentiated services. VOD arguably is even more complex and challenging than high-speed data. “I think the biggest challenge we face…is the fact that an integrated VOD system touches so many other elements of a system, and those are constantly changing,” says Steve Necessary, the president of the Xstream division of Concurrent Computer Corp. CableLabs, of course, has been the main driver in helping the industry fully engage VOD. Its metadata program uses the XML programming language to clearly define programming and create a hierarchy of information. The first metadata spec was released in February 2002. Updates were released in October 2002 and April 2003. Version 2.0 of the Asset Distribution Interface is expected this year. The goal is to lower encoding costs, further interoperability between equipment and systems from different vendors, increase reliability and enable systems to handle new or updated approaches to VOD. Batter up There are several ways in which VOD programming carrying the CableLabs’ spec reaches the operator’s main distribution point. In many cases, the content is “pitched” from the uplink—be it a TVN Entertainment Corp. or a discrete programmer such as HBO or Starz—and received by a “catcher” at the operator’s site. There are three other ways in which VOD content is imported into a system, says Joe Ambeault, the director of advertising for SeaChange International. Existing content can be encoded at the headend, events can be encoded in real-time at the headend and local programming—from networking affiliates or independent stations—can be delivered by file transfers or other means. These streams are “scrubbed,” or checked to ensure that the meta tags are accurate. Inaccuracies are corrected. This is key: A slight error in the title, for instance, could deliver an adult film into a folder for general audience distribution, a potentially embarrassing mistake. The programming is then ready for its distribution through the network to customers’ set-top boxes. Appropriate links to billing and other management systems also must be maintained. At that point, Ambeault says, the programming is transferred into VOD-compliant MPEG-2 bit streams for distribution. Simplicity for subs Each piece of the overall platform is evolving as the industry begins grappling with the great success that its VOD initiatives are enjoying. The most immediate goal is to enable subscriber access to programming in as easy a manner as possible. “The next big challenge is how to make the user interface better,” says Mark Hess, the vice president of digital television at Comcast. “When we have that much content, we have to be able to sort it very easily, have better search functionality. The current electronic program guides were developed for channels of television. [The designers] didn’t contemplate 10,000 hours of video.” Lanny Dietz, the senior sales account manager for interactive TV vendor IMAKE, says that a key advance in software management is the ability to make changes to meta tags from a centralized location. This, he says, can save tremendous amounts of time and labor. “For instance, the back office for Phillyvision can change the pricing for every movie from $9.95 to $7.95 with a couple of keystrokes. Without it, they would have to go into all the servers and change any number of pieces of content by hand.” Currently, Dietz says, Comcast uses IMAKE’s software. N2 Broadband offers products and services across the VOD spectrum. It has more than “pitcher and catcher” installations and/or provides back office software to Time Warner Cable, Adelphia, Cox, Charter and other MSOs. The company believes that the future lies with open standards, which will enable equipment from different vendors to interoperate, says chief architect Darryl DeFreese. This is a must in an era in which complexity is increasing and a steady influx of new vendors is entering the market. The most immediate challenge is developing open standards-based software that identifies problems before they impact subscribers. Models of distribution The industry is gearing up to go beyond the current meta tags, says Joe Matarese, the CTO of nCUBE Corp. For instance, he says, there is interest in standardizing the interface to the various billing systems—from DST Innovis, Convergys and CSG Systems—that serve the industry. There also is interest in standardizing the session setup and stream control interfaces, which manage how the set-top box talks to the VOD system. Iterations that go beyond the current CableLabs’ specs will include “trick files” that mimic VCR capabilities. The landscape on which the meta tags are being deployed and developed features architectures that are in a constant state of flux. There have been two waves of distribution models in VOD, according to Michael Pasquinilli and Nishith Sinha (Cox’s director of ITV technology and ITV systems engineer, respectively ). The first was the distribution of servers on a wide, as-needed, basis. The advent of high-capacity gigabit Ethernet transport mechanisms enabled the second—and current—wave, which features the centralization of servers and their connection to nodes via these high-capacity pipes. Saving bandwidth Cox is driving a third wave, which focuses on agile placement of content. The company has labeled its approach the Intelligent Asset Management System (IAMS). A top-10 movie, for instance, will be located closer to subs than a “library” film of limited popularity. The approach, which Pasquinilli and Sinha refer to as a hybrid, is based on the assumption that though it’s possible to use gigabit Ethernet pipes to pump as many events as necessary from a central source to an end user, it’s a wasteful use of bandwidth. Simply, that capacity can be better used for other purposes—even if it isn’t yet determined what those services will be. Cox will roll out the system during the first quarter in its San Diego system. The approach relies on a new generation of VOD servers from companies such as Midstream Technologies and Broadbus, and sophisticated software that can determine in real-time where the content should sit. This software, Sinha says, performs “predictive propagation” tasks. The software uses a set of operator-chosen parameters—usually focusing on a title’s popularity—to determine if it should sit at the hub or further away from consumers. It will continually reposition titles as usage patterns change. What’s in play going forward is what the standard interfaces between various elements of the overall VOD infrastructure will look like, Matarese says. Cable operators, from their earliest forays into full service networks, have developed an overall structure known as the interactive services architecture (ISA) for network management. The goal for ISA, which was championed by Time Warner, is to facilitate the ability of VOD management, communications infrastructure and server and asset distribution systems to work together. Another key element is a way of providing consumers the type of control of content to which they are accustomed. This may be provided by the digital storage media command and control (DSM-CC), which is part of the MPEG-2 “toolkit” and can provide VCR-like functionality. Agreeing to agree Currently, however, not much has been decided. “The general situation is that there is not enough agreement between everyone in the industry on what the standard interfaces ultimately should look like,” says nCUBE’s Matarese. “It may be that there will always be multiple architectures that can be deployed. It could be that Time Warner could use ISA and others may have different architectures.” In the final analysis, the entire infrastructure will have to support deep flexibility in both where content is stored and how it is presented. “The days when you sold a single movie at a single price are going to be limited,” says Dave Bartolone, the vice president of technology for TVN. “We’re going to look back and say, `Wasn’t it nice when we sold Titanic in St. Louis for $4.99?’ We’re going to have to sell it four different ways: Free with ads, $3.99 for just the movie, $4.99 with [DVD-like] extras and $19.99 with a game or CD. We will be striving to capture the person and upsell. Someday it’s going to be pretty complicated.” There’s nothing uncomplicated about the many challenges facing the industry as its VOD initiatives grow. Perhaps the interdependency of the complex web of hardware and software that comprise VOD makes it impossible to identify one element as the most important. “The bottom line is it’s a big chain, and a chain has to work all the way through,” says N2 Broadband’s DeFreese. “The big challenge for the industry is coming up with management standards for the diverse hardware and software components that have to work all the time.” Carl Weinschenk is a contributing editor at Communications Technology. Reach him at email@example.com.