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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