Orlando, Fla. -- With ongoing cable-system upgrades still
their priority, top engineers from major MSOs are eyeing ways to handle the demands of
bandwidth-hungry new services.
In a panel discussion at last week's Cable-Tec Expo
'99 here, top tech executives said they were focused on completing rebuilds and
upgrades that are essential to offering the "big three" of digital video,
high-speed Internet access and telephony over cable.
But as they scale their hybrid fiber-coaxial networks to
offer those advanced services over a broader customer base, operators are looking at
solutions such as node splitting and tools such as dense wave-division multiplexing to
enhance bandwidth and cut costs.
"The ability to scale the network is quite
simple," Charter Communications senior vice president of engineering Tom Jokerst
said. "It's the beauty and the power of the HFC architecture and the ability to
subdivide nodes and reuse bandwidth again and again and again, as much as you need, to
facilitate the service."
Tony Werner, executive vice president of engineering and
technical operations for AT&T Broadband & Internet Services (formerly
Tele-Communications Inc.), raised a stir by describing how his MSO plans to test a
"micro-node" cable-telephony architecture that pushes fiber optic transmission
to network depths of 50 to 75 homes passed per node, versus 500 or more under its current
Werner said the technology, developed by AT&T
Laboratories, uses digital and optical multiplexing to keep fiber counts low, pushing
maintenance and equipment costs down by reducing the number of active components, such as
power amplifiers, by 60 percent to 80 percent.
He also said the architecture was backward-compatible with
AT&T Broadband's existing HFC networks, and it did not necessarily rely on new
revenue streams from advanced services to justify deployment.
A pilot to determine the new structure's
cost-effectiveness will be run in a market he did not disclose, although it was rumored to
be Salt Lake City.
"It's cost-effective because you're reducing
fiber counts," Werner said. "We think there could be between a two- and
four-year payback just from distribution power and lower maintenance costs."
Alex Best, Cox Communications Inc.'s senior vice
president for engineering, echoed AT&T Broadband's interest in pushing fiber
deeper into the network due to the potential savings. But Cox figures that it could handle
500 to 1,000 homes passed per node, with extra fiber deployed as insurance where needed,
MediaOne Group Inc. has been working with 500-home nodes
while exploring architecture to go deeper than that, chief technical officer Bud
Wonsiewicz said. He estimated that for "pennies on the dollar" of the
operator's original upgrade costs, node subdivision could provide bandwidth increases
up to a factor of 64.
"It can be done neighborhood by neighborhood, so it
can be demand-led," Wonsiewicz said. "That's crucial for our race with DSL
[digital subscriber line]. The ability to promise people, 'If the cable passes your
home, we can serve you and we can give you the kind of bandwidth consumption you
need,' is a very important thing."
Interest in architectures for pushing fiber deeper into the
network transcended panel talks and moved through the exhibit floor, where a number of
vendors -- some already supplying AT&T Broadband -- were showing DWDM solutions to
support the demands created by telephony and other new, two-way services.
ADC Telecommunications Inc. -- which is supplying its
"Homeworx" cable-telephony gear to certain AT&T Broadband subscribers in a
Denver trial -- said AT&T Broadband raised interest in micro-node architecture at last
year's Society of Cable Telecommunications Engineers' Emerging Technologies
conference, and it did so again with its new trial plans.
"Now that Tony Werner's said they're going
to look at it, everyone's going to take a look at it," said Ham Mathews,
director of marketing for ADC's broadband-networks division.
Colin Boyd, vice president of North American sales and
marketing for AT&T supplier Harmonic Inc., saw a lot of foot traffic past such
displays as its new "DWDM-through-the-node" return transmitter, which is
intended to boost return-path bandwidth by eight wavelengths on a single fiber.
Boyd said AT&T Broadband raised operator interest in
DWDM. "Let's face it: AT&T's got a lot of influence on the industry
right now," he added.
The chief technology officers warned the packed audience at
the Orange County Convention Center that cable could not afford to be complacent about
broadband rivals such as DSL phone service.
Wonsiewicz used himself as an example. He can't get
cable-modem service in his Denver-area neighborhood, and he is a "satisfied DSL
customer." He reminded attendees that once the telcos surmount marketing and
technical hurdles, they'll have access to 60 percent to 70 percent of the market.
Best echoed that concern, acknowledging that the threat
will grow as the telco industry begins implementing simpler, standards-based solutions
such as the so-called G.lite DSL platform, aimed at promoting user self-installation in
place of a truck roll.
"I think we're in the driver's seat right
now, but in two, three or five years, DSL will be a formidable competitor," Best
Werner said cable needs to quickly move to an open
architecture and get cable set-tops packed with advanced functionality into the retail
channel to compete more directly against noncable devices that are already there, such as
EchoStar Communications Corp.'s "DISHPlayer" receiver with integrated WebTV
Networks service and digital hard-drive recording capabilities.
"We're walking a tightrope. If we don't go
as fast as possible, we'll have [EchoStar chairman] Charlie Ergen with his 500
channels and hard disk and all of the functionality we've promised but not
delivered," Werner said.