Manufacturers differ over division of digital TVs
eetimes.com
By Stephan Ohr
EE Times
(03/25/99, 5:33 p.m. EDT)
HASBROUCK HEIGHTS, N.J. — The architecture of next-generation television and video service systems took tentative shape at the 10th annual Digital Engineering Conference this week. The tenor of the panels and presentations revealed manufacturers' preoccupation with the partitioning between hardware and services — that is, the interface between digital televisions and the functions accessible via next-generation cable set-top boxes.
Sponsored by the Consumer Electronics Manufacturers Association (CEMA), the conference here reviewed the standards efforts under way in three major sectors of the consumer electronics industry: digital TV, cable set-tops (as dictated by the Open Cable Initiative) and the IEEE 1394 interface (under the purview of the 1394 Trade Association). The key issue, underscored at an evening panel session, was how much intelligence to put in the set-top box and how much to build into the DTV.
The manufacturers present, representing a broad segment of the consumer-electronics industry, agreed with the conjecture that there will be between 1 million and 2 million set-tops in use by 2001 — a small number relative to the number of televisions in use. Explaining the disparity, George Hanover of CEMA's engineering staff offered the wry observation that "the set-top box is an 'unnatural act' visited on the consumer."
Manufacturers appeared impressed by the "servers" — digital programming capture-and-replay devices — shown earlier this year at the Consumer Electronics Show by such companies as Tivo Inc. (Sunnyvale, Calif.) and Replay Networks (Palo Alto, Calif.). But there was scant agreement on the appropriate partitioning among set-tops, home servers and new-generation DTVs, or on how the consumer-electronics industry can pace rapid changes in technology that threaten to make current investments obsolete before their time.
Unlike personal computers, which have a life of 18 months or less, consumer televisions are considered a long-term design investment — and no one will invest in a high-resolution HDTV display when pixel formatting and aspect ratios are perpetually changing. "Pixels cost money," said Dave Kline, an engineer with JVC.
A paradigm shift, suggested by consultant Bernard Lechner, might partition new-generation DTVs into "two boxes" — a high-resolution, 16 x 9 display with a 10- to 15-year life span, and a $300 to $400 control console that could be upgraded every three years. The problem with that scenario, said Lechner, is that while the display constitutes the highest-value-added part of the system, the need to continually replace the electronics console would likely erode TV makers' margins.
The proposition for manufacturers is complicated by the Open Cable Initiative, a consequence of 1992 and 1996 legislation that allows end users to own their set-tops, rather than rent them from cable companies. The initiative makes it particularly difficult to come up with high-end platform standards, said Laurie Schwartz Priddy, former vice president of Advanced Platforms and Services at the Cable Television Laboratories consortium (CableLabs; Louisville, Colo.), who recently left that post to join cable giant Tele-Communications Inc.
"The cable industry is looking to proliferate new services, not new devices," Priddy said. "The challenge is to keep moving, to add functionality to bring appeal to high-end TV."
What Priddy called the "baseline model" would include one-way video services. Video-on-demand, including both special channel subscriptions and instant pay-per-view, is decidedly on the services list. "We know we can do video and the consumer will buy it — that's cool," she said.
But after that, what services will be most demanded — and what should thus go into the set-top — is uncertain. Docsis (data-over-cable-service interface specification) modems, two-way services and telephony services are being considered, as are software downloads.
A major concern of the cable companies is security and copy protection for restricted material. A business model under which consumers lease their set-tops from the cable operators allows the operators to control leasing of special-channel and pay-per-view descramblers. But with Open Cable, embedded security will be considered illegal after 2005. "A 'secret in the box' is not an option," said Priddy.
One solution is essentially a "lock and key" — a point-of-deployment (POD) security plug-in module — that the cable-system operator would supply to its customers. The POD would plug in to the consumer's set-top or DTV console. It would descramble secure digital video content and services in-band and would provide out-of-band signaling and control to the head end of the cable, according to Paul Zimmerman, who manages the system-integration effort at CableLabs. The POD would not be transportable; it would be bound to the set-top with which it was initialized.
Such manufacturers as General Instrument, Scientific-Atlanta and SCM Microsystems have responded to CableLabs' requests for information and are expected to be influential in POD-module development. FCC-supervised interoperability testing is expected to begin this year, and commercial products will likely appear in July 2000, said Zimmerman.
But Tom Wahlers' presentation of Open Cable firmware requirements set consumer-electronics manufacturers on edge. For video-on-demand, impulse pay-per-view, TV Web browsers and e-mail, the CableLabs' software consultant envisions Virtual Java Machines with HTML and Java Script interpreters. Consumer-electronics executives in attendance demanded that CableLabs specify the amount of memory required to execute those functions.
Before consumer companies can supply set-tops on the open market — either as standalones or as part of the DTV console — they will need to have a better idea of the hardware requirements and attendant costs, the executives said. Many worried that ease-of-use — the cable (and consumer-electronics) industry's "leg up" over the PC industry — will disappear, since consumers will need to be concerned with Mips, MHz and Mbytes in order to specify a cable box.
But CableLabs said those questions are difficult to answer, since no one yet knows what services the consumer will buy and since set-top manufacturers will be able to offer competing architectures.
"We don't have the keys if we don't own the box," quipped Priddy. |
