SAN JOSE, Calif. — Retailer Best Buy has conducted internal tests showing products certified under the guidelines of the Digital Living Network Alliance are not fully interoperable. The retail giant is considering withdrawing from DLNA, and word of the tests is beginning to spook others about adopting the group's guidelines.
The news comes at a time when DLNA is seeing a significant ramp in systems getting certified to wear its logo. The alliance was formed in 2003 to set guidelines to assure interoperability among a broad range of networked consumer, computer and communications systems.
Executives from DLNA said they were not aware of the Best Buy tests. However, they acknowledged shortcomings in interoperability of certified products, and said they have programs in place to address some outstanding issues.
Best Buy would not reveal details of the tests it conducted or their results. A spokesman who asked not to be identified said one of the problems was in the area of video.
"If one system uses a certain subset of optional DLNA codecs and another product uses a different set, how can they work together?" asked the Best Buy spokesman.
"DLNA is not the standard people were thinking it would be," said Stephen White, director of business development at Vizio, a rising digital TV maker, speaking in a panel discussion at the recent Connections conference. The Best Buy tests "set everyone back--we will wait a year until everything settles out" before certifying products for DLNA, he added.
Jaime Fink, vice president of technology and strategy at 2Wire Inc., a maker of residential gateways, said DLNA has both a historic opportunity and some nagging technical shortcomings.
Service providers can demonstrate their use of open standards by adopting DLNA on the residential gateway boxes they deploy to users' homes. That could help the industry avoid the regulatory struggles cable-TV operators faced creating open set-top box standards.
However, the DLNA guidelines currently are not ensuring interoperability, Fink said.
"Many DLNA devices do not see the data formats they expected to see" when linked to other systems on a home network, said Fink. "They should have never put intelligence in both ends" of devices on a home network, he added.
A new DLNA profile in the works could help address some of the problems. The Consumer Video Player Profile addresses how premium video content is brought to a digital TV. It currently specifies letting one device act as a server, responsible for rendering tasks, Fink said.
The new video profile could play a key role in next-generation residential gateways that send metadata from a service provider to a consumer's digital TV set, letting H.264 silicon in the TV render the video. Systems using that approach could appear as early as next year, he added.
DLNA executives confirmed the existence of the CVPP effort as part of a broader group led by representatives from AT&T and EchoStar. However, under DLNA rules, they were not permitted to share details about what it is working on or when it might be finished.
