While Tele-Communications Inc. has seen the
dense-wave-division-multiplexing light, other MSOs are less eager to jump on the
bandwagon, for now.
They agreed that DWDM technology is promising, but actual
deployment outside of TCI's ambitious, far-reaching embrace of DWDM is, for now,
InterMedia Partners used DWDM on one of its fiber paths in
Nashville, Tenn., to accommodate additional traffic, senior staff engineer Larry Warren
However, InterMedia has no plans at this time to deploy
DWDM elsewhere. "We're so far down the road with the technology that we're
using," such as dedicated 1310-nanometer lasers, Warren said, "that I don't
see any near-term, large-scale deployment of DWDM technology in our markets."
Pete Smith, Rifkin & Associates Inc.'s vice
president of engineering and new business, said that while his company is
"enthusiastic" about DWDM, it's "a technology that's useful when
you run out of fiber. We haven't had to face that issue."
Alex Best, senior vice president of engineering for Cox
Communications Inc., pointed out that his MSO has pretty much viewed DWDM as a valuable
tool that long-distance carriers have used.
Nonetheless, Cox has yet to deploy DWDM. "We're
still in the mode of having dark fiber available," Best said.
Last month, Harmonic Lightwaves Inc., General Instrument
Corp. and Antec Corp., among others, rolled out DWDM products targeted toward the cable
industry. They touted virtues such as being able to increase capacity to existing fiber
networks and to expand the opportunities for MSOs to offer enhanced services, such as
Internet access and telephony.
Although Cox has been an aggressive provider of Internet
and telephony services, "adding services has not dictated that our fiber capacity is
in jeopardy," Best said.
DWDM would become a viable expenditure, he added, if the
company was wildly successful in penetrating its markets with Internet access and
telephony -- so successful that a subdividing of nodes would be necessary. For now, with
1,000-home nodes in place, Cox has enough capacity in place.
Paul Gemme, vice president of plant engineering for Time
Warner Cable, explained that TCI is building "virtual hubs," while Time Warner
has established hub sites, "because we think that we're going to need some space
for servers and things of that nature further out into the plant."
Gemme said Time Warner is looking closely at DWDM.
"One could argue that it might be more cost-effective to deploy DWDM long-term,
primarily because you would use less fiber," he said.
At the same time, Gemme added, "you would still use as
many receivers, you would still use as many transmitters. To me, it's a
transport-to-a-hub issue," whether that hub is a virtual hub or a cabinet.
"You've still got to get fiber to each node."
Time Warner is using six fibers per node, with the
understanding that if demand dictates doing so, adding fiber to enhance capacity at this
time "makes a lot more sense" than deploying DWDM, Gemme said.
"It's not that we think that DWDM doesn't
have a place," he added. "We haven't found, in our network, what that place
is yet." With six fibers per node coming back to a hub site, Gemme is comfortable
with his network's capacity. Gemme also expects DWDM prices to drop, making it a more
viable option. With fiber running at between $3 and $3.50 per foot, plus an average
$1-per-foot labor cost, laying fiber is a cheaper alternative, he said.
"The 1310 lasers have been very, very dependable for
us," Gemme said. "We don't have long reaches because we run stuff out of
hub sites. Our longest glass run from a hub site in our distribution path is probably
Meanwhile, Warren said, his MSO is between 80 percent and
90 percent complete with a rebuild of its system, using 1310 lasers in every location.
"If we were in the beginning stages of our rebuilds,
it might make sense to go ahead and deploy it," he said. DWDM remains a possibility
if InterMedia acquires a cable system that needs a rebuild. "We'll use it on an
Except for its fiber path in Nashville, where DWDM is
helping to take fiber usage from 12 to two or three, "we're already in a
position to target services without the use of DWDM technology," Warren said.
The DWDM enhancement will allow for additional traffic,
including possible 1550-nm analog, as well as backing up hubs.
Gemme predicted that the first logical deployment of DWDM
for Time Warner will be to augment transport between hub sites.
"As we start to carry digital channels, I think that
it makes sense to start utilizing that fiber more and more," he said. "Will
[DWDM] ever find its way out to the distribution plant? I'm not sure yet. That's
where the costs are still prohibitive."