Broadcast Style Makes ITV Simpler

Thin is in these days as the U.S. cable television industry continues its digital transformation.

Most of the 15 million U.S. households with digital-cable services receive them courtesy of so-called "thin client" set-top terminals that complete a wide range of electronic instructions using limited processing and memory resources, at least compared to the prevailing information technology devices of today.

This isn't necessarily the way people thought things would be when the first modern incarnations of interactive television were dreamed up in the early 1990s. You'll recall that infamous experiments ranging from Time Warner's seminal Full Service Network in Orlando, Fla., to Bell Atlantic's Stargazer video-on-demand trials relied on reconstituted versions of full-scale PCs.

Dressed up to look like cable-TV converters, these powerful devices delivered far more processing muscle, graphics rendering capability and memory than today's digital cable set-tops can muster on their best day. There are reasons for that, of course, not the least of which is that the reported costs of the specially fabricated terminals used in Orlando were several thousand dollars per box.

The set-top isn't the only linchpin of cable TV's digital age that has turned out differently than many expected. On the network architecture side, there are profound differences between the way digital signals are distributed today and the way distribution was envisioned then.

Expensive ATM-style switches, for instance, have conceded a starring role on cable's digital stage to the more workmanlike and far more affordable technique of quadrature amplitude modulation. The computer-centric model of a vast server-to-client network — in which every subscriber household would command its own discrete allocation of bandwidth for every "event" appearing on the TV set — has given way, inevitably, to something slightly less revolutionary.

The modern cable delivery architecture still looks pretty much like the traditional broadcast model. Most video content originates from a core distribution point, and is sprayed, shotgun-style, across the network, so that it's available to every household in the exact same form at the exact same time.

So, does the collapse of the Internet-style model for television spell doom for ITV? Hardly. Today, millions of households around the globe have access to rich, satisfying suites of interactive content and applications, ranging from simple video enhancements to highly interactive video gaming and t-commerce.


Even as the supposed convergence of Silicon Valley and cable TV was in hyper-hype mode through the early 1990s, it seemed apparent that the raw economics of broadband delivery argued for an ITV system based, at least initially, more on the proven attributes of the broadcast model than the untested realm of a client-server platform.

Among other things, it seemed reasonable to assume that cable and broadband network operators would resist building an infrastructure in which they'd need to replace and upgrade digital terminals with the same relentless certainty we've all come to know (and dread) in the PC domain.

As a result, the broadcast model for ITV is laden with interactivity, but not always in the way the industry had first approached it. For example: You're at home, using your television to summon the latest headline bulletin from a richly designed interactive-news menu appearing on the TV screen. What appears to you to be a singularly devoted, one-to-one content session delivered on demand is, in fact, a cleverly disguised instance in which you've simply selected a data feed from an ongoing, broadcast stream of content. It looks like a discretely allocated session and feels like a discretely allocated session. But it's not. It's a broadcast application that hums its way to your TV set with minimal taxation of network and set-top resources. There is no Web browser involved. The content you're seeing looks like it was made for television, not a PC screen. And the words you're reading traveled to you over the exact same sort of MPEG-2 digital bitstream that delivers the Discovery Kids network or any other digitally encoded video source.

What's missing from this process? You've just engaged in an ITV session without ever sending an upstream data transmission of your own. What appeared to be a two-way interplay between you and the network was, in fact, purely a selection of a broadcast event. The articles you read were there on the data carousel all along, just as ESPN's SportsCenter
still exists even when you're not tuned to it.

The same process works not only for read-only news reports, but also for more elaborate interactive events. You can play along with a data application, for instance, that invites you to guess the winners of the Motion Picture Association of America's Academy Awards before they're handed out. Or try your hand at trivia games that congratulate you when you get the correct answer. You can even conjure up real-time sports statistics while you're watching a game.

But the truth is, we're dealing with what are fundamentally television networks, built for television viewing. We're recognizing that what connects the TV set to those networks is not a sophisticated workstation, but a very carefully engineered platform designed to meet rigorous standards both for cost and performance. We're also seeing that the business of pushing content to the home has been a very good for a very long time, ever since people like Milton Berle began doing just that, to wildly enthusiastic response, in the late 1940s.

Broadcast-style ITV is easily the simplest and most cost-effective way to deliver interactivity to the typical cable or satellite TV household. It also boasts a technological and economic feature rarely ascribed to ITV in the early days: scale. Whether the enhancement reaches one viewer or 100,000 viewers, each one of them is looking at the same copy of the content.

Does that mean you can't deliver on the loftier promises of ITV? Not at all. A wide array of advanced interactive features, such as t-commerce, electronic mail and messaging applications that underscore the "I" in ITV are successfully deployed worldwide. However, it also is certainly possible to introduce a rich ITV suite that operates largely from a broadcast posture.

It's also possible to inject lots of localism into the same sort of model.

While we were all busy formulating architectures for ITV delivery, a happy coincidence occurred. It goes by the name of extensible markup language (XML), a set of rules for manipulating Internet content that does wonders for the business of presenting local ITV content.

XML enables a cable system to gather updated Internet content and refashion it into easy-to-use templates that look terrific on the television screen. As these Internet content repositories are updated — with new weather reports, local movie theater listings, school activity calendars, local traffic conditions and the like — they're drawn into the broadcast carousel model, making the exact same, highly-localized content available at a just the click of a button on the remote control.

The magic of XML coupled with the appropriate ITV delivery platform gives cable operators a ready solution to what has always been a vexing problem: how to deliver meaningful, very current local information without breaking the budget.

The day will undoubtedly come when today's standard-issue digital set-top terminals have largely been dispatched to secondary TV sets in bedrooms and basements. Their replacements will likely be more capable boxes with fabulous enhancements such as DOCSIS (Data Over Cable Service Interface Specification)-compliant broadband modems, hard-disc personal video recorder attributes and more. All of these forthcoming features will do wonderful things for ITV, to be sure.

In the meantime, let's not forget that the current delivery platform for cable television is perfectly suited to bring the promise of ITV to millions of living rooms across America. It doesn't require state-of-the-art computers sitting atop the TV set. It doesn't necessarily even require a two-way return path. What it does require is a method of engineering properly for the way things are. Not the way we once thought they might be.