Electronic Design

The Connected Home Remains Stuck On Pause

Product advances continue to roll in, yet it's the potential standards convergence that may finally turn the tide for well-managed, consistent home multimedia delivery.

Multimedia nirvana is coming to the home... hopefully sometime in our lifetime. A flood of HDTVs, set-top boxes, home-theater PCs, and universal remotes (I have six, by the way) has poured into the market, yet getting them to play together is a challenge even a geek would like to avoid.

Nonetheless, the climate is improving. Next year, we’ll likely see a convergence around standards such as UPnP (Universal Plug and Play), DLNA (Digital Living Network Association), Gigabit Ethernet, and 802.11n. In theory, delivery of high-definition (HD) audio and video throughout the home will be possible across devices and from different vendors and content providers. Just about anyone will be able to connect devices together correctly on the first try.

Currently, audio and video content is available from a variety of sources, from on-demand movies via cable and satellite to Internet radio through a PC or dedicated network device. What’s lacking is any sort of coordinated or consistent interface for using and managing all of this content. Still, electronics stores will be packed with new ways to hear and view all of it.

Impending Tsunami
Riding atop the crest of the multimedia wave is HDTV. Now that HDTV is ubiquitous and a requirement in most parts of the globe, eyes and ears will be turning to other devices to complement this centerpiece.

The first point of contact is well established, with set-top boxes from cable and satellite companies being required for almost any type of HD content. On-demand and DVRs are standard fare, but these typically closed systems require other sources like DVD and Blu-ray players, home-theater PCs, and other sources to be connected directly to the HDTV through other inputs.

The latest in set-top box design is coming from companies like 2Wire. It’s looking to add to the sources of content as well as provide more interaction and services. Home security and home automation are just a couple of areas where a single box can act as a gateway for content as well as user control. Much of 2Wire’s work shows up on the back end, where providers need to be able to manage the new services.

Home-theater PCs like those based on Advanced Micro Devices’ AMD Live! Maui platform are becoming more robust with HDMI connections to displays and HD audio support (see “AMD Live! Home Cinema Platform” at www.electronicdesign.com, ED Online 20164). These often run Microsoft Vista and the Microsoft Media Center. They can also run MythTV, an extensible open-source DVR package, and commercial DVR software (e.g., SageTV).

Dedicated devices like set-top boxes and home-theater PCs will suffice for many. Still, there’s an expanding list of DLNA-based solutions that will change how people look at media distribution.

DLNA: THE TIES THAT BIND
DLNA is a standard built on top of UPnP, which is built on TCP/ IP (Fig. 1). As a result, DLNA can work over a range of networks, with Ethernet and 802.11 Wi-Fi as the typical transports of choice. Gigabit Ethernet and 802.11n provide the bandwidth necessary to deliver uncompressed HD video streams.

DLNA defines a number of device classes, including the media server, media player, media renderer, media controller, and media printer. An actual device can support multiple classes, although a typical DLNA environment will have at least a pair of devices, say, a media server and a media player.

A media renderer and player can display content, with the renderer being controlled by a media controller. The user of a media player can select its content from a media server. Also, as noted, a device can incorporate multiple classes. For example, a PC could provide its local content as a media server, display content via a media player, and be controllable from a remote system by providing media-rendering services.

Many consumers will think of portable media players when looking for DLNA media players, but devices like Samsung’s LN40A750 LCD HDTV are changing the game (Fig. 2). Besides delivering top-notch video, this HDTV sports a 1-Gbyte RJ45 Ethernet connection in back with a DLNA-compatible media player built in.

Older Samsung devices could handle audio and images via a USB port, but this HDTV can stream movies from media servers, including D-Link’s DNS-321 Network Storage Enclosure (Fig. 3). The DNS-321 can handle terabyte drives like Seagate’s new Pipeline HD drive. The SATA II drive is designed to handle up to 12 HD streams when used in a DVR. The DNS-321 will be limited by the Ethernet connection.

Several DLNA media players hide under the guise of gaming machines. For instance, the Sony PlayStation 3 can stream content from DLNA devices on the network in addition to playing Bluray movies and streaming content from the Internet.

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The latest Microsoft Windows Media Player can turn a PC into a DLNA media player and server. Unfortunately, the latest incarnation of the Windows Media Center doesn’t have the same level of integration with DLNA. On the other hand, a Windows Media Extender device like D-Link’s DSM-750 Wireless HD Media Extender is tightly integrated, matching it in terms of interface as well as control (Fig. 4). Expect DLNA support to reach this level in the future.

Part of the challenge is DLNA’s architecture. It relies on UPnP A/V (audio/visual), which in turn uses SOAP and XML. The XML SOAP messages are sent via HTTP, giving DLNA devices at least a small built-in Web server. Broadcasting is used quite heavily within the protocol. However, given the amount of bandwidth needed for audio and video streaming, this overhead should be negligible. It’s also used primarily for service identification.

DLNA interoperability testing will be interesting. DLNA defines hundreds of profiles for compliance. This is required because of the large number of formats and codecs involved. Operational issues can arise when a format/codec mismatch occurs between a source and destination.

DLNA also defines things at the nuts-and-bolts level, leaving the user interface to the application. This means features like playlist support, third-party transcoding, scheduling, and linking devices together for operations such as coordinated streaming from a source to multiple devices by a third-party controller will be challenging when possible.

Another issue is the target environment itself—the home. Security and management is a much different problem than in a corporate office. UPnP and DLNA may not be happy campers or welcome in these environments, but the ease of logical connection between devices is still desirable. Whether a corporate version or extension of DLNA will arise is open for speculation. One way or another, it needs to be addressed soon.

In fact, these issues will show up in the home where devices with different purposes are combined. For example, parents may allow their children to use their audio and video content across the network, but not allow them to hook into the home-security or home-automation system.

DLNA is in its infancy and initial support has been workable, though unpolished. Open-source projects like MythTV, MediaTomb, and GeeXBoX uShare have DLNA support. Like most commercial products, MythTV provides DLNA support as a secondary feature. This is changing as products like Samsung’s LN40A750 include DLNA support as a primary feature. The uShare DLNA server is now part of the Ubuntu distribution, so Windows and Linux now have DLNA support, too.

Likewise, USB and UPnP stacks are standard fare. However, the availability of DLNA middleware from Allegro Software and others makes it much easier to deploy DLNA-based products.

Allegro Software’s RomPlug Toolkits address the range of DLNA classes as well as different levels of sophistication. For example, audio devices can often be based on low-end microcontrollers, a far cry from a fully loaded PC. Allegro Software also addresses the Internet gateway, since UPnP is designed for a local home network only.

The DLNA standards continue to evolve. Content management, user interface, and digital rights management are in the mix and being refined as well. There’s now enough of a standard to create robust products with Sony, Samsung, and others leading the way. Of course, plenty of current products provide the kinds of services that DLNA will deliver, though they utilize proprietary protocols.

A MIGHTY WIND
Streaming audio can find its way into places other than a PC. Logitech’s Squeezebox Boom (Fig. 5), Roku’s SoundBridge, and Sonos’ ZonePlayer, for instance, are network-based audio players that can stream MP3 files and Internet radio almost anywhere.

The Squeezebox Boom includes Ethernet and 802.11b/g support. Its four speakers are driven by a 30-W digital amplifier with Stereo XL technology to widen the virtual soundstage. Six buttons for station/playlist presets, a remote control, and a seven-day alarm clock lets you wake up to different sounds every day. The designers of this unit definitely thought about the box’s placement, because it includes ambient light sensors that automatically dim the LCD control panel.

Available at SlimDevices.com, SqueezeCenter is open-source software that runs on a number of operating systems, like Windows and Linux. It can deliver local content such as MP3 files and forward streams from other sources like Internet radio stations.

SqueezeCenter can run on some NAS devices, such as Net- Gear’s ReadyNAS. Although SqueezeCenter isn’t a DLNA device yet, it can access content on network drives. Moreover, many DLNA-capable media servers provide this service.

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The Squeezebox Boom is one of a family of players that streams content from a SqueezeCenter. A SqueezeCenter must be running for the Squeezebox Boom to work, but Logitech’s squeezenetwork.com can provide this function, too. Users can sign up for a free account and manage their playlists in the same fashion as with SqueezeCenter. SqueezeNetwork is handy when taking the Boom on the road.

The Sonos ZoneBridge provides functionality similar to SqueezeCenter. The difference is that it comes in a standalone box. Sonos’ design expertise can be seen in its dual-port Ethernet switch, which makes wired support easy since only one network cable need apply. If an Ethernet device (e.g., laptop) is already there, then it plugs into one port of the ZoneBridge and the cable into the other. Sonos players can also operate in synch, providing room-to-room audio coverage from a single control.

Playback is the primary purpose of these systems. However, the user interface is critical to success, especially for managing playlists and accessing Internet sites and podcasts. This is where DLNA will likely fall short initially, since it doesn’t address this issue. Logitech, Roku, and Sonos have extensive partnerships with content providers, allowing users to simply select content from a variety of lists with the click of a mouse or press of a button.

Streaming audio works very well even from the Internet because the bandwidth requirements are low compared to connections such as DSL, cable, and fiber. Video is a much different story.

MORE MOVIES
Streaming video from a local source such as a DLNA media server over a Gigabit Ethernet network or 802.11n works well. Getting video from the Internet doesn’t perform quite as efficiently, depending on the Internet connection. DSL can be marginal, and cable connections work well if the rest of the users on the cable drop aren’t all downloading lots of content. Fiber, such as Verizon’s FiOS, is likely to have plenty of bandwidth for streaming video.

Roku’s Netflix Player performs real-time streaming (Fig. 6). Netflix customers, who can already watch movies on their PC, can use this box in the same manner. And, it’s designed to connect to HDTVs. Customers add movies to their viewing queue using a PC and Web browser before they can watch them on the Netflix Player or a PC. A lower-quality picture is delivered if the connection speed is insufficient for a high-def stream.

One way to provide a consistent user experience is to cache the movie with a hard disk. Vudu and Apple TV take this approach. Both can drive an HDTV. The Vudu XL has a 1-Tbyte hard drive, enough to store 500 standard-definition (SD) movies (Fig. 7). HD movies would cut this by almost a factor of 10.

Unlike the Netflix Player, Vudu customers can select movies using the remote control and the on-screen interface. A selected movie is stored on the hard drive. It can be viewed immediately if the Internet connection has sufficient bandwidth to deliver the movie in real time, as is the case with the Roku unit. If not, playback will not start until enough of the movie has been buffered on the hard disk. This allows uninterrupted playback. Internet users will already be accustomed to this process, though buffering a YouTube video clip takes a couple seconds at most.

An alternative is to have the movies download in the background. In this case, the user can select from a collection of movies on the hard drive for immediate viewing.

Vudu uses its own TruFilm compression technique to reduce download bandwidth and storage requirements for HDX movies. It delivers 1080P 24-frame/s video and 5.1 audio support on par with HD Blu-ray disks. DVD and Blu-ray disks already use compression, but TruFilm takes the process further. Vudu rents new movies in HDX format for $5.99 ($3.99 for older titles). Rentals can be extended for a week for $1.99.

DVRs like TiVo’s HD XL DVR also provide this type of service. TiVo customers download movies to the DVR’s hard drive as well as record television shows from cable or over-the-air transmissions.

All of these platforms could easily handle DLNA media servers if the design has sufficient headroom. Most already provide all of the store, decoding, and management services. Some, like TiVo’s offerings, have already been upgraded to offer movie downloads. It’s clear that the hardware and software will just be part of the puzzle.

Because content and content delivery are key, Vudu, Netflix, TiVo, and Apple have developed this part of the distribution infrastructure. It’s also clear that digital rights management (DRM) is a major hurdle. One issue we didn’t examine was movement of content (such as a movie) between, say, a DLNA media server and a portable media player (e.g., the Archos 5).

TAGS: Components
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