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case study Extending DS3/STS-1 Signals to the Demarc and Beyond Situation 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 efficiency 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. Solution 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 provides 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. Wall-Mount Chassis with extension brackets Rack-Mounted Chassis Selection Criteria 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, basements, 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 highvalue 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 doors. 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. Conclusion 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 network. 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. 2 Network Element DSX O/E Line Extender Singlemode Fiber Optic Cable up to 15 Kilometers (9.375 miles) Network Element DSX O/E Line Extender Central Office or High-Rise Business Office Building E3/DS3/STS-1 Optical Line Extender Used in Multi-floor Central Office and Collocation Environments Centralized Campus Headquarters Singlemode Fiber Optic Cable up to 15 Kilometers (9.375 miles) Network O/E Line Extender Element Remote Building Network Element DSX O/E Line Extender Remote Building Remote Building E3/DS3/STS-1 Optical Line Extender Used in Building Local Exchange Carrier (BLEC) and Campus Environments 3 Web Site: www.adc.com From North America, Call Toll Free: 1-800-366-3891 • Outside of North America: +1-952-938-8080 Fax: +1-952-946-3237 For a listing of ADC's global sales office locations, please refer to our web site. 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