Yes, you were right in burying the pipe.
Fiber Optics Go the Last Mile
By Charlotte Wolter
New optical last-mile technologies, shown at the National Fiber Optics
Engineering Conference (NFOEC) in Chicago in September, are looking to
leverage the large reservoirs of dark fiber in metropolitan areas to create
a new way to provide high-bandwidth access.
These products use a dark fiber, or wavelengths, in a metro dense
wavelength-division multiplexing (DWDM) system linked to passive opticals
for the last mile, and they provision services with an intelligent switch in
a central office (CO), location. Because the link between the CO and the
customer premises is not a synchronous optical network (SONET), but native
asynchronous transfer mode (ATM), services can be provisioned quickly and
are highly scalable.
According to market research firm Vertical Systems Group, Dedham, Mass., 76
percent of businesses in North America are within one mile of a fiber
source. Sources of that fiber include dark fiber competitive local exchange
carriers (CLECs), such as Metromedia Fiber Network Inc., White Plains, N.Y.,
regional Bell operating companies (RBOCs) and even digital loop carrier
(DLC) links, which typically include several dark fibers.
Adding to the availability of dark fiber is the September Federal
Communications Commission (FCC) ruling requiring incumbent LECs (ILECs) to
sell or lease their dark fiber plant to CLECs as unbundled network elements
(UNEs).
However, most businesses have not been able to take advantage of that
resource because the cost of existing fiber technologies, such as SONET, can
be justified in the last mile only if there is demand for very large
bandwidth.
An economical last-mile fiber technology enables CLECs to tap large
multitenant buildings and business parks, says Jeff Gwynne, vice president
of marketing, Quantum Bridge Communications Inc., North Andover, Mass.
Quantum Bridge is planning to introduce products that combine a low-cost
passive optical last mile with an "optical access switch" in a CO or
headend, and an "intelligent optical terminal" at the end user's premises.
The system uses ATM switching over the passive optics from the customer
premises to the CO to aggregate traffic efficiently and provide quality of
service (QoS). The customer premises equipment (CPE) has multiple
interfaces, including 100BaseT Ethernet, T1 and ATM, and can take output
from integrated access devices (IADs). Interfaces at the CO to the backbone
include ATM over SONET, IP over SONET or gigabit Ethernet.
Another startup, LuxN, Sunnyvale, Calif., provides what it calls "managed
optical physical layer access." It also combines an intelligent CO device
linked to CPE over low-cost fiber links, but concentrates intelligence in
the CO. The CPE box is more like an optical channel service unit (CSU) with
multiple ports, says Eugene Park, director of strategic marketing at LuxN.
It will be available in single-user or multitenant configurations.
Marconi Communications Inc., Irving, Texas, which recently acquired local
loop company RelTec Corp., Cleveland, and ATM specialist Fore Systems Inc.,
Warrendale, Pa., has a consumer applications fiber-to-the-curb technology
that builds on the company's experience in DLC.
Called DISC*S (Digital Intelligent Subscriber Carrier System), the product
brings fiber to a remote digital terminal, but then, unlike DLC, continues
fiber to within 500 feet of a customer. Each local loop fiber serves an
average of 7.5 homes and delivers 24 DS-0s, up to 750 megahertz (mHz) of
video (the equivalent of 125 analog television channels or about 600 digital
channels) and 10BaseT Ethernet data.
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