For a major service provider in Canada providing services both as an ILEC and CLEC, DS1 remains a
viable business—not a growth business, but one with a large number of circuits and operating efﬁ-
ciency that helps DS1s remain proﬁtable. Recently, however, demand for DS3 services both to and
beyond the demarc has become a more common service request. For this service provider, ﬁnding
solutions for these applications was not the challenge. The challenge was to deploy extended-reach
DS3 solutions today that would not threaten operating efﬁciency and network reliability as the
number of DS3 circuits in the network grows.
The service provider’s standards committee selected ADC’s Extend
Optical/Electrical Line Extender
solution for applications that require DS3/STS-1 signals over distances up to 15 km (9.375 mi) without
use of repeaters. Where the 900 foot distance limitation prohibits use of copper, the predominant
uses of the Extend solution are as follows: extending DS3 service beyond the demarc within buildings
or multiple buildings in a campus; and delivering DS3 from the central ofﬁce to the customer site.
The Extend O/E Line Extender is a carrier-class system that includes a rack-mount chassis for up to
24 DS3/STS-1 modules as well as a wall mount chassis that holds one or two DS3/STS-1 module.
Both the rack-mount and wall mount chassis use the same bidirectional, plug-in style DS3/STS-1
module. A/B power feeds support redundant power and full alarm capability. Each module also pro-
vides status LEDs for power, transmit failure and receive loss-of-signal for each channel.
Operationally, the Extend system is a simple product — a factor that greatly appealed to the service
provider in solving distance issues associated with DS3 services. On one end of a circuit, the
DS3/STS-1 module converts an electrical signal into an optical signal for transport over singlemode
fiber. At the far end of the circuit, the DS3/STS-1 module converts the optical signal back to electrical.
One local and one remote module together serve as a dual regenerator to extend the distance of a
single DS3/STS-1 circuit.
Extending DS3/STS-1 Signals
to the Demarc and Beyond
with extension brackets
When compared to competitive products, the Extend O/E Line Extender excelled in several aspects.
First, it was apparent that ADC offered a superior system for cable management. Copper and ﬁber
cables are clearly separated — DS3/STS-1 input and output terminations are on the rear of modules;
optical transmit and receive connectors are located on the front. In addition, the minimal-proﬁle wall
mount unit includes an integrated ﬁber storage spool that prevents haphazard looping and coiling of
ﬁber cables in remote locations that shorten service life of ﬁbers and disrupt service. The integrated
ﬁber storage also adds a more professional appearance for such remote locations as closets, base-
ments, CEVs, and other tight spaces.
The rack-mount chassis includes cable support bars on the rear for coax cables and radius limiters on
the front for protection of ﬁbers terminated at SC connectors. With installation of vertical cable guides
on the front of the rack, guides that use no rack space, optical ﬁbers can be safely routed to splice
decks and storage trays.
The second factor that helped gain approval of the Extend O/E Line Extender was density of the rack
mount chassis, a feature that affords greater ﬂexibility in providing service to customers. The Extend
chassis supports 24 plug-in modules and, with advanced heat dissipation features, does not require
use of valuable rack space for such external devices as cooling fans and air ﬁlters to maintain proper
operating temperature. Reliance on fans to cool DS3 modules was deemed too risky for such high-
value circuits. In addition, integrated cable management features of the Extend O/E Line Extender use
no additional rack space and present a minimal rack proﬁle that does not impede closing of cabinet
Finally, ﬁeld trials conﬁrmed that the Extend O/E Line Extender was simple to install and conﬁgure.
With no training or complex software administration required, the operations department was able to
reduce installation time and ease turn-up of service.
With ADC ﬁber frames already deployed across the network, the service provider was already well
aware that proper management of ﬁber cables breeds reliability and operational efﬁciency into the net-
work. The features that characterize all ADC ﬁber solutions — including high density, superior cable
management, modularity, and ease of service turn-up — carried over to the Extend O/E Line Extender.
The ADC solution was the preferred product for building reliability and operational efﬁciency into the
growing inventory of DS3 circuits.
Singlemode Fiber Optic Cable
up to 15 Kilometers
Central Office or High-Rise
Business Office Building
E3/DS3/STS-1 Optical Line Extender Used in Multi-ﬂoor
Central Ofﬁce and Collocation Environments
Singlemode Fiber Optic Cable
up to 15 Kilometers
Centralized Campus Headquarters
E3/DS3/STS-1 Optical Line Extender Used in Building Local
Exchange Carrier (BLEC) and Campus Environments
ADC Telecommunications, Inc., P.O. Box 1101, Minneapolis, Minnesota USA 55440-1101
Speciﬁcations published here are current as of the date of publication of this document. Because we are continuously improving our products, ADC
reserves the right to change speciﬁcations without prior notice. At any time, you may verify product speciﬁcations by contacting our headquarters
ofﬁce in Minneapolis. ADC Telecommunications, Inc. views its patent portfolio as an important corporate asset and vigorously enforces its patents.
Products or features contained herein may be covered by one or more U.S. or foreign patents. An Equal Opportunity Employer
1274852 10/03 Original © 2003 ADC Telecommunications, Inc. All Rights Reserved
Web Site: www.adc.com
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