Networking ADVANCED NETWORKING TECHNOLOGY More power to the bottom line Next-generation services require high-amperage power protection By David Schomaker, Senior Product Manager, Connectivity Business Unit, ADC Telecommunications C able television has changed. No longer just a medium for delivering television signals, it has evolved to de- liver the most advanced multimedia services in communications. Multiple system opera- tors (MSOs) are building and rebuilding their networks to compete with local telecommunication companies for revenue- generating high-speed data and primary line services. As these next-generation services de- mand higher levels of bandwidth, high-am- perage power protection becomes increas- ingly critical for network integrity. Integrating new, current-hungry, high- speed data network elements into a cable network can cause havoc for cable televi- sion operators. With manufacturers incor- porating higher density electronics and components into smaller-sized packages, custom-configured power distribution plat- forms are necessary to accommodate not only the high amperages, but specific re- quirements of various applications. A well-conceived powering platform will save money, resources, and customers, especially when using cable modem ter- mination systems (CMTS), laser transmit- ters and receivers to deliver enhanced data and carrier-class primary line telephone services. Keeping customers happy and reducing churn is critical for operators. And an effective power distribution plat- form can produce immediate results. Power to the people MSOs have traditionally used AC pow- er at the headend, while their telephony counterparts have used DC power. But as ca- ble networks delve into the telephony realm, operators are powering much of their re- vamped network with DC power to preserve services even during power outages. Telephony is a lifeline service–subscribers de- mand immediate, always-on services. When 99.999 percent service reliability is not only expected, but also required, preemptive troubleshooting is critical in maintaining customer satisfaction. Missing the sec- ond half of a fa- vorite television program may be an- noying for cable viewers, but failing to complete a 911 call can have grave consequences for telephony subscri- bers. That is why ca- ble operators now take extra precau- tions to protect and distribute power in their networks by installing high-am- perage protection platforms. In today’s busi- ness environment, every decision af- fects the bottom line. Cable operators must make prudent, proactive decisions. The impact of power protection and dis- tribution platforms on network integrity can no longer be overlooked. A reliable platform minimizes operational costs, pro- tects vital, revenue-generating equipment, and ensures the delivery of advanced mul- timedia services to customers. Pump up the amperage Today’s critical cable network elements re- quire power. Lots of it. Manufacturers are packaging more complex components and electronics into smaller network elements. Asked to do more, do it in less space, and do it more efficiently, operators are incorporat- ing high-amperage power distribution plat- forms into the headend to preserve rack space, slow network expansion and optimize the functionality of high-density equipment. Cable telephony is potentially the most lucrative piece in the converged triple play of data, voice and video services. A crit- ical element to its ul- timate success re- sides in the perfor- mance of CMTS units. Designed to handle the opera- tional, management and service demands of today’s competi- tive cable television marketplace, this technology serves both high-speed data and telephony traf- fic. It is a perfect ex- ample of a high-den- sity network element designed to meet to- day’s high-band- width requirements. Cable operators can increase their profitability by increas- ing the number of throughput ports in a CMTS. Many of the newest, most effective CMTS units have twice the number of ports from previous architectures. This technological breakthrough has also dou- bled the amount of power required. Whether it’s the electronics, components or the fans required to cool it, contemporary CMTS units require a high-amperage pro- tection and distribution platform to en- sure continuous revenue growth. Distributed power Cable television operators are beginning to deploy cable network solutions com- prised of several technologies incorporated Figure 1: Varying amp equipment. into a single rack to accelerate the delivery of high-value broadband services. This trend has led to a greater reliance on flexible pow- er distribution platforms. Most of these rack solutions feature CMTS units and RF trans- mitters and receivers that require amperage protection. Even though routers, demarca- tion points, lasers, amplifiers and transport equipment may not be included in these cable network solution racks, they still re- quire DC power distribution and protection. And all the network elements feature dis- parate amperage allotments. Some applications now require more than 70 amps of distributed DC current per net- work element. Previously, a battery distribu- tion fuse bay (BDFB) may have provided this amperage directly to each network ele- ment in the rack. This method wastes pre- cious BDFB positions. Each run from the BDFB creates another expense for opera- tors. Running one cable from the BDFB to a power distribution panel can save expenses. The best power distribution platforms now provide up to 200 amps in a single rack unit and include various output amperage ca- pabilities to ensure each network element is fed sufficient current–at a cost commensurate with the requirements. Most installations re- quire both high and low amperage. Effective power distribution platforms deliver various amperages to accommodate the specific re- quirements of each network element, helping improve network integrity and efficiency. Reliable power Power is often treated as a commodity, at least until disaster strikes. A power outage can be devastating to a cable television op- erator. Without power, key network ele- ments become inoperable and service is jeopardized. Subscribers are quick to jump to another provider if they are dissatisfied with the quality and reliability of their current service. Cable television operators are sub- sequently revamping existing headends and hubs with DC-powered functionality in an at- tempt to shore up and maintain reliability. Each cable network is unique, but the most reliable and cost-effective networks use combinations of AC and DC power to ensure compatibility with specific elements and applications. AC powers television programming hardware. Enhanced data and telephony elements tend to rely on DC power. There is no hard-and-fast rule–operators often go with the method that they are most comfortable with or the one that delivers the best-perceived val- ue. DC power costs more to deploy, but it better accommodates the specific require- ments of advanced services such as cable telephony more effectively. Many cable operators regard DC pow- er as an investment that minimizes failure points and speeds repair time. The more time it takes to repair, upgrade and install equipment, the more profit margins are eroded. Personnel costs skyrocket and cus- tomer satisfaction wanes. Designed to lim- it failure points and improve redundancy, a DC-powered network helps foster con- tinuous service, resulting in lowered oper- ational costs and increased revenue. Heading to DC DC power begins the same way AC does, as an alternating current from a gen- erator. It is then converted to DC at the headend through the use of rectifiers. Eventually DC power is fed to the prima- ry power panel, which in turn feeds the bat- tery distribution fuse bay (BDFB). If ex- ternal power were to fail, the batteries con- tinue to power network elements without a service lapse. The rectifiers also keep the battery banks charged in case of an AC power failure at the initial feed destina- tion. This built-in redundancy enables net- work elements connected to multiple feeds to preserve service integrity, even if a par- ticular power source fails. A higher power The cable television industry is boom- ing. And as it ramps up to meet subscriber demands, its service offering is becoming more complex, requiring increasing amounts of power. Advanced services, new technological innovations and revenue- generating opportunities are readily avail- able. But all can be lost with the flick of a switch unless a reliable and flexible power distribution platform protects the vital ca- ble equipment in the headend. With many CMTS units featuring twice the throughput capacity of previous models; laser, amplifier, transport and routing equip- ment transitioning to DC power; and cable television networks now delivering lifeline telephony services–absolute reliability is critical. Revenue-generating equipment must be powered and protected to maintain and grow continuous revenue streams. Subscribers demand always-on service. Successful cable operators provide it. ■ Networking ADVANCED NETWORKING TECHNOLOGY Figure 2: Power distribution scenarios. E-mail: David_Schomaker@adc.com Reprinted from CED, June 2002 by Reprint Services. Copyright © Reed Business Information, a division of Reed Elsevier, Inc. All rights reserved. For reorders call Reprint Services 651.582.3800. For subscription information call 303.470.4800. 1236386 223801 . from a gen- erator. It is then converted to DC at the headend through the use of rectifiers. Eventually DC power is fed to the prima- ry power panel, which. have used DC power. But as ca- ble networks delve into the telephony realm, operators are powering much of their re- vamped network with DC power to preserve services