|Digital TV Over DSL: A
BY LAURA GUEVIN
Broadband Internet connectivity for home and enterprise users certainly
holds promise in the market for converged services. The ability to
transfer data, video, and even voice over one speedy connection will soon
be the rule, and not the exception. Digital Subscriber Line (DSL) access
offers this promise using existing copper phone lines. If subscribers are
within three miles of a Digital Subscriber Line Access Multiplexer (DSLAM,
usually located in a telco's central office), they can enjoy voice and
data access over one line (if the current phone line meets certain
Digital television (DTV) is another enhanced service that can be added
to that mix, and one that is gaining popularity (see Michelle Clarkin's
online column "PBS
over IP," for an overview of how PBS is implementing it). With
most television stations jumping on the bandwagon and offering at least
some programming in digital format, viewers can now appreciate the quality
and interactivity that come with this exciting technology.
DTV is an alternative broadcast format to the current analog broadcast
signals. It offers movie-quality video and CD-quality sound at its most
basic. DTV is more efficient than analog technology, and allows
broadcasting using less channels than analog, freeing up part of the
valuable broadcast spectrum for other uses like public safety. Congress
has already authorized the distribution of additional broadcast spectrum
to each television broadcaster for DTV, so they may simultaneously offer
digital and analog broadcasting. And the FCC has set a rollout schedule
for the technology, projecting most residents will have the option to
access it by 2002.
DTV NORTH OF THE BORDER
New North Media (formerly NBTel, an Aliant
company) understands the value of DTV, and has already added some bundled
offerings to its bag of long-distance and Internet services. According to
Joe Mosher, general manager of interactive television for New North, the
company started market trials for DTV in the greater New Brunswick, Canada
area in September, and launched the service commercially in January. He
said they expect to be servicing 84,000 homes by October.
For New North, offering DTV service was just a natural extension of the
company's game plan. They first planned to offer it in 1993, but Mosher
says the technology just wasn't ready then. Now, DTV opens the door for
all sorts of enhanced services. "It isn't about cable TV, it's about
taking interactive services to another appliance in the home," he
says. It also gives New North an opportunity to focus on new services,
rather than haggling with other long-distance companies over rates.
"We're getting out of this commodity game of lowering prices one cent
a minute every week. Price wars at commodity levels don't do anything for
The actual installment and setup of the hardware and software to make
DTV a reality was fairly simple for New North. Mosher said the company did
due diligence and reviewed software from several vendors before making a
decision. But many vendors offered expensive, proprietary end-to-end
solutions, and New North already had an extensive telco network in place.
They wanted a flexible solution based on open IP standards that could
easily integrate with their current hardware and network investments. They
chose New Brunswick-based iMagicTV
to provide the server and client-side software necessary to deliver DTV.
The first thing New North had to do was set up head-end capability in
order to broadcast. According to Mosher, the beautiful thing about
iMagicTV's DTV Manager software is that infrastructure is transparent to
it, so they could use their existing network to connect to the head-end.
Their head-end and content servers are actually housed 150 miles away from
their service area, and yet they use their existing fiber ATM network to
connect to their DSLAM. New North bundles DSL modems and the set-top boxes
necessary to pull in DTV with its service (most televisions still don't
have DTV connectivity built in, and a special box is required to receive
the service, whether it is through cable or DSL). They use Alcatel DSL
modems and Pace set-top boxes with iMagicTV's client software installed.
Mosher says New North is working to keep up with access demand, and the
current two-kilometer loop length around a DSLAM shelf will yield transfer
rates of about six Mbps for each customer.
ADDING VIDEO TO THE NETWORK
Marcel LeBrun, president and CEO of iMagicTV, describes the company's
software as an interactive TV service platform. The server software sits
in the provider's network, and runs on Sun Solaris boxes. It's 100-percent
Java-based on the back-end, for portability. The software is built on IP
as the abstraction layer, and therefore whatever comes in under the IP
layer doesn't matter, in terms of interoperability. The server can sit in
a centralized or distributed location, and LeBrun says service providers
usually keep it in a static location like a network management center.
The client software, which is installed on a set-top box or a PC (for
DTV viewing directly through your computer) is pared-down Java, based on
C++. Basically, the digital video stream is encoded in MPEG format at the
head-end, and is sent over the telco network. The set-top box communicates
with the head-end over the network, and requests a certain channel. For
access on a television, the software also offers an interactive Web
portal, and video on demand. It basically defines the channel according to
user preferences, and not a spot on the broadcast spectrum. Therefore, a
channel can be a Web site or a television station. The software works with
many set-top boxes, and the company has partnerships with Motorola
and Pace Micro of Europe. It can
work with any box that supports MPEG, and may be managed remotely, over
THE VALUE OF SERVICES
LeBrun says that two-way, interactive voice and video services are already
enabled using iMagicTV's software, although few service providers are
rolling them out yet. He says that being able to access the Internet
through your television set is not terribly exciting, but the control and
convenience that DTV brings is where the value comes in. "I think the
really compelling stuff is microbroadcasted new media entertainment,"
says LeBrun. He believes the Web will become an extended distribution
network for television, and a powerful value-added service for providers.
As for adding two-way packetized voice over DSL to the mix, LeBrun
believes regular analog phone conferencing will win out for the time
being, especially if customers are able to do it over the same copper wire
they are using for video and data. But distance learning and video
conferencing are applications that hold promise for DTV.
iMagicTV is releasing a new software product called Timeless TV, which
would basically take the place of a VCR. It would record shows and call
them up at the customer's request, using one-to-one microbroadcasting.
LeBrun says DSL is better able to support one-to-one capabilities than
cable or satellite right now, giving it a slight advantage in the DTV
market. However, he believes services will be the ultimate differentiator
when it comes to providing infrastructure.
Mosher agrees, and says that while cable companies in New North's
service area are also offering DTV, there's more elegance and
interactivity in the DSL offering. He said the company also plans to offer
VoIP -- when market acceptance for it reaches a better level. Right now,
New North offers 121 channels of audio and video in addition to high-speed
Internet access. Other services include sports and weather on demand, an
interactive community page (to replace the scrolling text channel offered
by most cable companies), and a self-service white pages directory. They
also offer e-mail, although the technology is currently better for
receiving than sending messages since all work is done using a remote,
which brings up a pop-up keyboard on the screen. Mosher says they are
working on a better interface to encourage more interactivity.
New North is also working on the second release of their portal, and
they have plans to add two-way video, voice mail, and caller ID services.
Mosher says the new release should be ready by the first quarter of 2001.
He thinks TV commerce will be the next big draw but stresses that he
wouldn't want this service to fall into the trap of the push broadcast
model. Rather, viewers would be able to buy what they want, when they
want. LeBrun echoes those sentiments, and believes the dotcom community
will lead the evolution of DTV, citing AOL TV, Amazon.com, and eBay as
examples. "I believe that all of these dotcom market leaders will
begin to develop TV strategies. Broadcasters will move a little bit
The ultimate selling point for DTV will be its ability to deliver a
broad range of services. DSL is an efficient way to deliver those
offerings now, although the transport mechanism of the future will be
transparent and irrelevant to the end user. What will matter will be the
convenience of receiving voice, data, and DTV over one reliable pipeline,
with the converged billing and pricing scenarios that come with them. The
communications providers who have the best services and the most valuable
packages will be the real winners in the burgeoning DTV market.
Laura Guevin is Managing Editor of Internet Telephony magazine. She
welcomes your comments at email@example.com.