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Backing for DVI Standard Could Cloud HDTV Picture

8/05/2001 8:00 PM Eastern

Depending on one's perspective, the consumer high-definition television market was either clouded or boosted when a diverse group of interests recently voiced their support for the Digital Visual Interface (DVI) security scheme.

DVI is considered a supercharged method for protecting high-definition transmissions from the set-top box to the TV monitor from content piracy.

The announcement has helped DVI to emerge as a strong competitor to the Institute of Electrical and Electronics Engineers' IEEE-1394/Digital Transmission Content Protection (DTCP) interface and security scheme, which has already won support from a number of companies and organizations, including the Consumer Electronics Association (CEA).

DTCP is also known as 5C, for the five companies that produced the standard: Hitachi Ltd., Intel Corp., Matsushita Electric Industrial Co. Ltd., Sony Corp. and Toshiba Corp.

The introduction of DVI into the high-definition video-security mix "does clutter the product battleground and creates confusion among content owners and device manufacturers," said Richard Doherty, director of research for Envisioneering Group. "DVI has cluttered the clarity of what seemed to be a very clear decision," he said, in reference to 5C.

Behind the engineering and interface discussions, however, the stakes are huge. The prospect of perfect, digital high-definition copies of Hollywood films is the stuff of studio executives' nightmares.

And Hollywood could leverage this fear into a DVI-protection requirement in negotiations over pay-per-view and video-on-demand rights, according to Doherty.

Jumping aboard the DVI bandwagon last month: Cable Television Laboratories Inc., DirecTV Inc., EchoStar Communications Corp.'s Dish Network, Fox Entertainment Group, the Satellite Broadcasting & Communications Association, Sony Pictures Entertainment, The Walt Disney Co., Thomson Multimedia and Warner Bros.

"The primary reason behind [the initiative] is to ensure more HDTV content from the studios, and this is a step in that direction," said James Harper, a spokesman for Thomson Multimedia, which makes high-definition televisions as well as HDTVs with integrated DirecTV receivers. "Anything we can do to ensure more HD content is in our best interest.

But it's far too early to predict when Thomson would incorporate DVI into its sets, he added.

The adoption of DVI by direct-broadcast satellite operators is on the horizon. Next year, all DirecTV-licensed consumer-electronics manufacturers are slated to incorporate a DVI connector with high-bandwidth digital-content protection (HDCP) into the DBS provider's enabled high-definition digital set-tops. Likewise, Dish Network will adopt DVI/HDCP in its next-generation HDTV set-tops.

On the cable side, "we believe support of DVI will complement the cable industry's support of the 1394 interface with 5C copy protection, which dates back to 1998," CableLabs president and CEO Richard Green said in a statement. "Cable is still committed to the 1394/5C interface, and intends to support both DVI and 1394/5C on set-top boxes designed for connection to high-definition television sets."

Set-top box maker Motorola Broadband Communications Sector could not be reached for comment about DVI support.

However, Sony's interactive digital-cable receiver — to be used in Cablevision Systems Corp.'s digital-cable rollout — contains a HDTV "pass-through" with a 1394 port and DTCP. Doherty expects other cable TV set-top makers — including Motorola and Scientific-Atlanta Inc. — to begin demonstrations of DVI or 1394/5C security features at this year's Western Show.

The emergence of DVI raises the issue of which method is more secure — DVI/DTCP or 1394/5C.

"DVI is more secure than 5C, almost solely for the reason that it's a very fast pipe," Doherty said. In other words, data travels from the set-top to the TV set so fast that today's receive-and-record technologies can't keep up.

"To Hollywood, that makes sense," Doherty said. DVI supports uncompressed video and runs at hundreds of megabits per second — faster than satellite and digital-video streams, or a personal video recorder's ability to capture them.

This contrasts with 5C, a security method that relies on "secret-key" encryption. The DTCP scheme supports full and restricted authentication, as well as authentication, exchange and content keys.

There's a statistically miniscule but theoretical possibility that pirates could obtain the keys. However, if the keys are kept secret, then the content is secure.

Keys can also be changed for each segment of a broadcast, said Doherty. 5C "has an awful lot of strength to it" and it is in widespread use, he added.

According to the CEA, both Sony Pictures Entertainment and Warner Bros. have agreed in principle to support DTCP.

Price is another key difference between DVI/DTCP and 1394, Doherty pointed out. It only costs $1 or $2 to implement 1394 in a set-top, but DVI can cost in the "tens of dollars," adding significantly to set-top component costs.

On the surface, DVI appears to be the stronger security method. But it's weakened by trends in both silicon development and low-cost storage or hard-drive technologies that could crack the DVI speed threshold by mid-decade, Doherty noted.

The CEA was conspicuous in its absence in voicing support for DVI. The trade group — which adopted 1394/DTCP as its security standard this spring — is developing a voluntary labeling program for 1394 products due for completion this fall, said CEA manager of communications and public policy Jenny Miller.

The labeling program includes the development of graphic "descriptors" to help consumers in selecting interoperable digital video products with 1394 interfaces that utilize DTCP.

Despite its commitment to 1394/DTCP, Miller said the CEA "will consider new technologies and new systems."

DVI "will be something we'll look at," she said. The emergence of DVI "shows [the industry's] commitments to content creators' concerns."

 

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