Picking Up the Pace on OpenCable


The cable industry, faced with impending ITV applications from a News Corp.-owned DirecTV Inc., is quickening its work on the OpenCable Applications Platform — the middleware specification developed by Cable Television Laboratories Inc. that will allow MSOs to offer interactive applications.

Two speakers at the Society for Cable & Telecommunications Engineers' Emerging Technologies conference on Jan. 15 in Dallas sketched out a roadmap as to how cable operators can deploy interactive applications not only on newer digital video recorder and HDTV set-tops, but also on the millions of legacy 2000 series set-tops from Motorola Inc. and Scientific-Atlanta Inc.


Cox Communications Inc. ITV systems engineer Steve Calzone explained that at present, some current set-top boxes run advanced applications, such as DVR, electronic program guides, video-on-demand and HDTV.

"OCAP implementations are appearing in MSO labs," he said. "But on the downside, application options are low and test costs high."

And, at the moment, current hardware is not OCAP-compatible. "The [Motorola] DCT-1000 and 1200 are not viable. OCAP [set-tops] will only account for a small portion of the overall population for at least the next five years.

"There are 30 million set-tops and no standards for interoperability between the two main platforms and no standard application development platform."

EchoStar Communications Corp.'s Dish Network, for example, uses software from OpenTV Corp., while DirecTV is using DVB-MHP.

The cable industry employs Motorola and Scientific-Atlanta set-top software, while middleware stacks from Microsoft Corp. and Liberate Technologies Inc. are also floating around.

A further challenge is the wide range of set-tops deployed — even within the Motorola and S-A families — with a range of random-access memory, processing speeds, video scaling, pixel depth and graphics resolution. Middleware has to be written to handle all those differences.

"It's a challenge and difficult to deal with," Calzone said. "Some lower-end boxes are just not good enough, they are too slow, and don't have enough memory to run a middleware platform to support Java. But the 6208 and 8000 are close."

"The solution is to make the most of deployed legacy platforms and define an on ramp for OCAP to provide cross-platform interoperability," said Vidiom Systems chief technology officer Eric Miller.


That on-ramp, he said, is based on the Java and DVB-MHP specs already inherent in OCAP.

"Over 30 million set-top boxes could run a single unified API," Miller said. "Java is the cornerstone of standards-based application development."

The key is to "develop a simple Java-based API set which will reach down to the DCT-2000, but have enough richness to enable more interesting applications on mid- and high-tier set-tops," Miller said.

At the same time, there is a need to provide resident applications — like legacy programming guides —with "back doors" to circumvent the most onerous performance bottlenecks.

Miller said the java.lang back door would cover core objects and data types, while Java.io would handle file and streaming data support. Java.util would cover timers, dates, iterators, hashtables and vectors. Java.net would handle networking primitives for definitions for URLs.

In addition to that base "class list," Miller said a list for TV is being developed.

This software includes javax.tv.graphics, plus the extensions: .locater, .service, .util and .xlet. These would support tuning, media selection, video display control, extended timers and the Xlet application framework.

Final pieces in the software would be the OCAP/MHP classes. Miller said those classes would support Java TV tuning classes and be used for discovering video parameters, power status and other applications.

This Java software sits between the native port layer on the set-top.

Above the Java stack would sit the resident set-top applications, such as a guide and third-party applications.

Under the Java software stack would sit the native port layer of the set-top. That port layer sits on both the resident set-top operating systems and the device drivers, which sit on the actual set-top itself.

The benefits to using Java as an on-ramp are many, Miller said. Such a single-legacy solution would provide for cross-platform interoperability and give developers an easy OCAP upgrade path. It would reduce development and test cycles, containing costs.

"There are millions of set-tops that can run Java today," he said. "It can run on DCT-2000s, and provides the best alternative for efficiency in spending 'app' dollars. The [Java] on ramp is one of the best solutions to getting us to that point."

There are talks "with other MSOs and manufacturers to move through this and make it happen," Calzone said. "There are no grand answers at the moment, but we hope to get to it quickly. Ultimately, we want to go to Sun and everyone else in the industry."

Added Miller: "Cox has tried to build a consensus to get a sense that this is a viable space."