Sony's Smyers said that the ad hoc Coral Consortium has already released a specification for passing content between different DRMs. Thus, he considers the DRM interoperability problem solved. "The technology already exists. It's just a convention for orchestrating multiple services," Smyers said.

However, the Coral approach has yet to be implemented in products that are shipping. "In some cases, people may need to develop business rules for things like content that people have already purchased. But from a deployment perspective, it's [an open] question" who will use the technology and when, Smyers added.

Green of Cable Labs said the cable industry has been "pretty carefully" watching the Coral Consortium's work. Describing the consortium's progress as "slow-moving," Green said that the "multi-industry, multimanufacturer" initiative is not so easy to pull off "unless there is a huge market driver."

Stu Lipoff, partner at analyst firm IP Action Partners (Newton, Mass.), expects that "a common DRM for all services and all consumer delivery platforms will come long after 2007." Predicting a phased-in approach, Lipoff said, "I expect DRMs for Internet content downloads will continue to be proprietary for clusters of devices."

The first step toward a common DRM will be for content servers to support multiple DRMs, he said. The second step will likely mirror the next-generation cable set-tops, in that devices--starting with PCs--will support multiple DRMs. In the end, consumers only care that they can get the content they want on a range of devices and move it between them. For that, "you don't need a common DRM," Lipoff said.

Networking the home

Despite the rise of 802.11n broadband wireless links in 2007, Wi-Fi will be no panacea for the digital home. Other wired and wireless solutions will come on strong this year. They include coax-based approaches from the Multimedia over Coax Alliance (MoCA) and Home Phoneline Networking Alliance (HomePNA), the power line-based HomePlug 2.0 and various flavors of ultrawideband.

Lipoff noted that supporting whole-house networking on the order of 160 feet with data rates of 200 to 540 Mbits/ second makes 802.11n "a very attractive candidate for home media networking capable of carrying multiple HD [high-definition] video channels."

But Lipoff cautioned that in some cases, the RF pathway required by 802.11n will not work due to shielding by walls, interference from other sources or just long distances.

Indeed, "11n will make streaming audio better and video possible--as long as you are not using your microwave," said Smyers of Sony, who spent years promoting 1394 as a unified home net. "But I still think the digital home will be a heterogeneous environment, and no one physical layer will win."

ST's Lagomichos predicted that cable and satellite operators are likely to prefer wired technologies such as MoCA in the United States and HomePlug in Europe. IPTV operators may pursue wireless solutions such as 802.11n more aggressively, he said, but "reliability for HD signals is an issue."

Daniel Marotta, group vice president of Broadcom Corp.'s communications group, predicted that 802.11n will emerge as a critical technology for home networking. "The speed that .11n brings and the additional bandwidth are going to be key for some wireless delivery options that weren't previously possible," he said.

According to NXP's Kleingeld, 802.11n is one of several standards that will be used to enable home networking. "Eventually it doesn't really make a difference what standard is being used," he said, adding that consumers clearly don't want to add more wires. Thus, the solution either needs to make use of existing wires, through technologies such as HomePlug, or be wireless, like 802.11n.

The service providers are calling the shots in home networking for set-top-box makers, who see themselves as agnostic, said Dave Davies, vice president of strategy and product marketing for Scientific-Atlanta's digital set-tops. "The cable op- erators are more interested in MoCA, the telcos focus on MoCA and HomePNA-over-coax, and others are thinking about HomePlug," said Davies. "So we'll see multiple flavors of home networks in 2007."

However, service providers see wireless as expensive, insecure and unreliable. They fear costly service calls due to routine interference as well as thefts of service from apartment owners picking up a neighbor's wireless TV signals. Thus, Scientific-Atlanta has no plans to integrate any wireless networking in its set-tops this year, though it does already sell Wi-Fi peripherals that attach via USB.

"I personally see wired nets taking off in 2007. They will definitely start shipping in volume, but no one will be in the tens of millions for the next couple of years," said John Hussey, vice president of the high-speed signal-processing group at Analog Devices.