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January/February 2007 BICSI news advancing information transport systems PRESIDENTвЂ™S MESSAGE 3 EXECUTIVE DIRECTOR MESSAGE 4 BICSI UPDATE 41-42 COURSE SCHEDULE 43-44 STANDARDS REPORT 45-46 Volume 28, Number 1 Building a Redundant and Resilient College Network 14 How to Work with the Authority Having Jurisdiction 22 The Wi-Fi Path Loss Equation and Antenna Specifications 26 Increasing Power Margin with High-Performance Optical Fiber 34 Testing Multimode Optical Fiber: Importance of Controlling Launch Conditions 38 2007 BICSI Officers PresidentвЂ™s Message PRESIDENTвЂ”John Bakowski, RCDD/NTS/OSP/WD Specialist; St. Catharines, Ontario, Canada; 905.646.5100; firstname.lastname@example.org PRESIDENT-ELECTвЂ”Edward Donelan, RCDD/NTS Specialist; Telecom Infrastructure Corp.; Pawling, NY; 845.855.4202; email@example.com SECRETARYвЂ”Peter P. Charland III, RCDD/NTS/WD Specialist; CET ITS Consulting; Framingham, MA; 508.868.9080 ; firstname.lastname@example.org TREASURERвЂ”Brian Hansen, RCDD/NTS Specialist; Leviton; Rosemount, MN; 651.423.9140; email@example.com U.S. NORTHEAST REGION DIRECTORвЂ”Christine Klauck, RCDD/NTS Specialist; SIEMON; Watertown, CT; 860.945.5889; firstname.lastname@example.org U.S. SOUTHEAST REGION DIRECTORвЂ”Charles (Chuck) L. Wilson, RCDD/NTS/OSP Specialist; Wilson Technology Group, Inc.; Brooksville, FL; 352.796.9891; email@example.com U.S. NORTH-CENTRAL REGION DIRECTORвЂ”Jerry L. Bowman, RCDD/NTS Specialist, CISSP, CPP; CommScope Enterprise Solutions; Columbus, OH; 614.853.3812; firstname.lastname@example.org U.S. SOUTH-CENTRAL REGION DIRECTORвЂ”Michael Collins, RCDD ; AT&T; Bellaire, TX; 713.567.1234; email@example.com U.S. WESTERN REGION DIRECTORвЂ”Steve Calderon, RCDD/NTS/OSP Specialist; I T Design Corporation; Westlake Village, CA; 805.777.0073; firstname.lastname@example.org CANADIAN REGION DIRECTORвЂ”Richard S. Smith, RCDD/NTS/OSP Specialist; Bell Aliant Regional Services; Moncton, NB Canada; 506.859.3106; email@example.com EUROPEAN REGION DIRECTORвЂ”Brendan вЂњGregвЂќ Sherry, RCDD/NTS/WD Specialist; Qualitas Limited; Hertfordshire, UK ; +44 1708 733 032; firstname.lastname@example.org EXECUTIVE DIRECTORвЂ”David C. Cranmer,RCDD; BICSI; Tampa, FL; 800.242.7405 or 813.979.1991; email@example.com COMMITTEE CHAIRS: BICSI CARESвЂ”John Discenza, General Cable Corp; Weston Ontario, Canada; 416.791.2401; firstname.lastname@example.org вЂў CODESвЂ”Phil Janeway, RCDD; Time Warner Telecom; Indianapolis, IN; 317.713.2333; email@example.com вЂўEDUCATION ADVISORYвЂ”Michael Collins,RCDD; SBC; Bellaire, TX; 713.567.1234; firstname.lastname@example.org вЂў EXHIBITOR ADVISORYвЂ” Kurt Templeman, Sumitomo Electric Lightwave; Research Triangle Park, NC; 919.541.8100; email@example.com вЂў ETHICSвЂ”Carl Bonner, RCDD/OSP/WD Specialist; Network Communications Supply Company; Milton,FL; 850.626.6863; firstname.lastname@example.org вЂў INSTALLATIONвЂ” Daniel Morris, RCDD; Kitco Fiber Optics; Virginia Beach, VA; +1 757.518.8100; email@example.com вЂў MEMBERSHIP & MARKETING ADVISORYвЂ”Edward Boychuk, RCDD; Convergent Technology Partners; Flint, MI; 810.720.3820; firstname.lastname@example.org вЂў NOMINATINGвЂ”John Bakowski, RCDD/NTS/OSP/WD Specialst; St. Catharines, Ontario, Canada; 905.646.5100; jbakowski @bicsi.org вЂў REGISTRATION & SPECIALTIES SUPERVISIONвЂ”R.S. вЂњBobвЂќ Erickson, RCDD/NTS/OSP/WD Specialist; Communications Network Design; Haysville, KS; 316.529.3698; email@example.com вЂў STANDARDSвЂ”Theron J. (T.J.) Roe, RCDD; Garrett Com, Inc.; Hockessin, DE; 302.235.0995; firstname.lastname@example.org вЂў TECHNICAL INFORMATION & METHODSвЂ”David P. Labuskes, RCDD/ NTS/OSP Specialist; RTKL Associates, Inc.; Baltimore, MD; 410.537.6070; email@example.com Seize the Day The phrase Seize the Day, which appears in music, movies and literature, means many different things. For me, this term is a recommendation on lifeвЂ”that time is short and we all should make the most of what we have and what we have been given. Seize the Day should also be an important beacon for everyone working in the information transport systems (ITS) business. John Bakowski, There are some individuals who see limits in RCDD/NTS/OSP/ our line of work. After all, a lot of IT managers and WD Specialist CIOs remain preoccupied with the more visible firstname.lastname@example.org and glamorous active equipmentвЂ”even though none of the routers, cameras and controls will operate without a properly designed, installed and tested cabling and wireless infrastructure. However, when you look closely at the ITS business today, you will see that we actually work in an industry with more limitless opportunities than ever. This holds true whether you are an apprentice in ITS, the owner of an established design/build contracting firm, or systems integrator. On one hand, there are so many directions you can take as part of the ITS industryвЂ”foreman, designer, building owner, trainer, product manager, consultant, project manager, business owner and many others. These are all opportunities available to you, assuming you want to seize them by growing your own ITS knowledge, experience and skills. On the other hand, the scope of ITS is broadening, especially for usвЂ” the specialists with entirely unique talents around cabling and wireless infrastructure. A dozen years ago, we all pretty much worked with voice and data systems. Now, BICSI members install the infrastructure and hardware for security, AV and building automation systems (BAS), anything that is IP centric. As a result, BICSI members are in an enviable positionвЂ”it seems the complexity of our business makes it easier for us to master the other ITS disciplines, rather than vice versa. Again, this is opportunity for the takingвЂ”for those who seize the day by taking courses and training, and earning new credentials, to advance their career. If you really take Seize the Day to heart, you know that none of us is limited by what we know today, that all of us has the potential to grow and learn, whether it is for income, self-fulfillment or career development. It is comforting to know that you work in an industry that offers so many avenues for development and advancement. The opportunities are out there for youвЂ”if you choose to seize upon them. Looking Forward to 2007 I want to thank David Cranmer, RCDD, for accepting the position of Executive Director for BICSI. We are thrilled to have DavidвЂ™s combination of strong management practices, integrity and industry knowledge to guide the staff. I also want to thank the volunteers who write training content and manual chapters, and work on other committee projects, to help evolve the products and services for the membership. BICSI members are the ITS professionals who are positioned best to capitalize on convergence in the marketplace; it takes volunteers like you to create the learning platforms we all need to Seize the Day. Lastly, I thank the BICSI staff for working through a difficult year of changes without losing their professionalism and high standards. We canвЂ™t do it without you. . BICSINEWS January/February 2007 03 BICSI Executive Director Be Careful What You Wish For Many of you may remember that I lived in Tampa for about 10 years from 1994 to 2004 and, David C. Cranmer, during that time, the goal had RCDD always been to move to email@example.com California to retire. But in 2006, after being in northern California for less than two years, imagine my surprise when I got a call from BICSI President John Bakowski asking if I would be interested in coming back to Tampa and serving as the interim Executive Director for BICSI. I confess it was not an easy decision. I spent a great deal of time pondering the pros and cons of the offer but, in the end, I was honored to serve as the interim Executive Director. I even went so far as to tell John that I would not put a time limit on the appointment so that the Executive Director Search Committee would not feel any undue pressure to find a permanent replacement. Upon arrival in Tampa last June, some board members asked if I would submit my name to the search committee as a candidate for the permanent position. This turn of events was a horse of a different color. More sleepless nights ensued as I struggled to come to grips with returning to Tampa and giving up my business as an expert witness to take over this huge responsibility. To give you some historical perspective, I attended my first BICSI conference in 1980 and over the years I have served on the Board of Directors and a term as its president. I also have been a contributing author on the Telecommunications Distribution Methods Manual (TDMM), Customer-Owned Outside Plant (CO-OSP) Design Manual, and the Information Transport Systems Installation Manual (ITSIM). In addition, I chaired the Installation Committee from its inception, audited BICSIвЂ™s Authorized Training Facilities, spoke at conferences and many other duties that I canвЂ™t even remember as of this writing. The point is that I have a long history with BICSIвЂ”volunteers, members and staffвЂ”and I feel a certain responsibility to this fine association. Because of these feelings, I agreed to have my name submitted. 04 Advancing Information Transport Systems www.bicsi.org Well, you all know the outcome. I was appointed Executive Director, effective January 1, 2007. However, I want to assure all of you that the Executive Director Search Committee did a thorough job of evaluating all of the candidates to find the right person. I thank them for their confidence in me. In retrospect, accepting the position at BICSI was an easy decision. After working with BICSI for 26 years, I have a deep-seated connection with the information transport systems (ITS) industry and its members. Already, I have made changes to strengthen our staff and its responsiveness to members and volunteers. Our strategic plan sets a path for continued growth both in the U.S. and internationally, but it takes industry people to understand many of its nuances. Because BICSI needs industry people in key positions to effectively implement this plan, I recently hired back Richard Dunfee as Director of Professional Development and Credentialing and IвЂ™m confident of his ability to guide that group. At BICSI World Headquarters we understand our job is to serve the Board of Directors, volunteers and the membership at large. On staff, we clearly recognize that without the direct input and guidance from volunteers and committees, the association would become weak. I assure you that you can expect the quality of everything we do, from manuals to member services, to continually improve. The last half of 2006 was good for BICSI and its members and we look forward to even more success in 2007. If you ever feel the need to complain, complement or just chat, IвЂ™m always available. I look forward to working with all of you in 2007. . 4USFOHUI 4USFOHUI 4QFFE 4UBNJOB 0QUJDBM$BCMF$PSQPSBUJPOJTDPNNJUUFEUP IFMQJOHZPVTVDDFFEGPSUIFMPOHSVO Superb engineering designs make the worldвЂ™s best cable. And that makes for fewer problems after installation and better performance, even in the most demanding conditions. вЂў Optical Cable Corporation is dedicated to the manufacture and sale of the highest quality tight-buffered п¬Ѓber optic cables for high bandwidth transmission of data, video and audio Call 1-800-622-7711 to simplify your most complex communications challenges. communications. Optical Cable CorporationвЂ™s п¬Ѓber optic cables are designed for campus applications for use indoors and outdoors, simplifying installation, reducing costs and improving reliability. Tight-buffered п¬Ѓber optic cables are the clear advantage for all critical communication networks. 5290 Concourse Drive вЂў Roanoke, Virginia, USA 24019 Phone 540-265-0690 вЂў Canada 1-800-443-5262 www.occfiber.com On the Cover ... ... Smart Card Essentials for Physical Access Control Contactless smart cards offer applications beyond simple access. BY MARK PETERSON 06 Advancing Information Transport Systems .... ... ... N ew technologies can create market confusion as designers, installers and end users struggle to identify the elements that enable effective product evaluation and deployment. This is evident as contactless smart cards become the de facto standard for physical access control. Although MCU-based (microcontroller unit or chip) smart card development began back in the mid-1980s, only recently is the pace of smart card adoption in the physical access control market surpassing other legacy technologies. As market demand continues to increase, those who design, specify or deploy smart cards for physical access control are looking beyond marketing hype to identify the factors that will ensure a valid contactless smart card deployment for their customers. www.bicsi.org ... Historically, the limited functionality of legacy card and card reader technologies (e.g., magnetic stripe, bar code, Wiegand, and low frequency proximity) made product choices relatively easy. For the most part, these technologies are single purpose: transferring card data to a reader and the reader in turn sending the data to a back-end access control system (controller and application software) to make an access decisionвЂ”granting or denying access based on the cardholderвЂ™s access privileges. Therefore, historically product choices were driven in large-part by product availability, reliability, brand confidence and customer service. Today, contactless smart cards provide a far more advanced technology platform that increases product performance and expands smart card use into other business processes beyond physical access control. To choose the right product, it is essential to have a solid understanding of todayвЂ™s smart card technology and its capabilities. Drivers for Smart Card Growth There are several reasons why smart cards are becoming so popular for use in physical access control systems. One of the most topical, and sometimes most controversial, is the U.S. GovernmentвЂ™s post 9/11 mandate for increased Personal Identification Verification (PIV), incorporating the use of a smart card based on the governmentвЂ™s Smart Card Interoperability Standard. As mandated by Homeland Security Presidential Directive (HSPD-12), the National Institute of Standards (NIST) BICSINEWS January/February 2007 07 has issued the Federal Information Processing Standards (FIPS) Publication 201-1: Personal Identity Verification for Federal Employees and Contractors, 2006 March. Publication 201-1 specifies the architecture and technical requirements for a common identification standard for federal employees and contractors. The overall goal is to achieve appropriate security assurance for multiple applications by efficiently verifying the claimed identity of individuals seeking physical access to federally controlled government facilities and electronic access to government information systems. As with many such activities, the commercial marketplace follows suit as the government leads the way in setting the standard. Several other factors are facilitating the trend toward smart card adoption. With an increase in public attention to the protection of personal data, the built-in data security features offered by smart cards are becoming very popular. Smart cards also provide the ability to not only read data from a card, but also to write data to a card. This increased data storage creates a platform for diverse applications to store specific data on the same card. This feature makes smart cards a valuable tool for deploying biometric technology since biometric templates can now be stored on the card. The result is a single card that can securely store access control data, biometrics template data, cashless vending data and other data, increasing the overall value of the card across other aspects of the customerвЂ™s business. Yet with all of the increased data security and operational flexibility smart cards provide, one of the most powerful market drivers of smart card adoption is cost parity with legacy technologies. Contactless smart cards offer a significantly enhanced feature set along with superior data security at essentially the same cost of the legacy 125 kHz Prox (low frequency proximity) technology. Although still a viable technology, there is no significant reason to use 125 kHz Prox for new installations. Comparing Smart Card Technologies By far, the legacy technology of choice for physical access control cards and readers has been 125 kHz Prox. With this technology, a radio frequency identification (RFID) chip and antenna are sandwiched inside an ISO standard sized card. When the card is presented in the electromagnetic field of the card reader (thus powering up the chip), the card format data is transmitted via RF to the card reader. This proven and reliable RFID technology became popular primarily due to its ease of use and reduced maintenance characteristics due to no moving parts. Prox is based on de facto industry standards rather than any ISO or IEC standards. Chart 1. Comparing smart card technologies. 08 Frequency 13.56 MHz 13.56 MHz 125 kHz Standards ISO/IEC 14443 ISO/IEC 15693 None Read Range Up to 10 cm (2-3 cm typical) Up to 1 meter (6-8 cm typical) Up to 1 meter (6-8 cm typical) Memory Capacity Range 64 to 64K Bytes 256 to 4K Bytes 8 to 256 Bytes Data Transfer Rate (Kb/sec) Up to 848 Up to 26.6 Up to 4 Read/write ability Read/Write Read/Write Read only Mutual Authentication Challenge/ Response Challenge/ Response No Advancing Information Transport Systems www.bicsi.org ... Some of the characteristics of 125 kHz Prox are: вЂў 125 kHz operating frequency вЂў Read only вЂў Up to one meter read range вЂў 4 Kbps data rate вЂў 8- 256 Byte memory storage вЂў Vendor dependant data security As compared to contact smart cards, contactless smart cards provide the physical access control market with vastly superior functionality while providing an identical user interface to the widely deployed 125 kHz Prox technology. This familiarity of use makes contactless smart cards a natural next generation solution for physical access control. TodayвЂ™s contactless smart card products are, for the most part, a plug-and-play replacement for 125 kHz Prox. Contactless smart card products operate in the same mannerвЂ”access system components are wired the same way and they use the same card formats (internal card numbering sequences) of legacy technology products. This allows designers and installers to easily deploy contactless smart card technology in new installations as well as migrate legacy systems toward using contactless smart card technology. Most importantly, contactless smart card technology is a standards-based technology. The two most recognized contactless smart card standards are ISO 14443 A/B and ISO 15693. While these standards deploy similar operating characteristics, ISO 15693 is viewed by many as more conducive to physical access control due to its ability to provide longer read ranges, which is more like those the market is familiar with when using 125 kHz Prox. Chart 1 compares operational characteristics of 125 kHz Prox with both ISO 14443 and ISO 15693 technologies. It is important to note that being standards-based only creates the potential for interoperability. Being standardsbased does not ensure interoperability. In fact, in the case of contactless smart cards, once the cards are properly and responsibly provisioned (meaning data is stored in specific memory location(s), and the keys used to protect the data are changed to be unique to that deployment), the contactless smart card solution is essentially proprietary to that customer. For example, a MIFARE or DESFire (14443 brand names) solution purchased from one source most likely will not be compatible with a MIFARE or DESFire product purchased from another source because the data size, location and security will be different from supplier to supplier. Some end users have found out the hard way assuming that selecting a technology used by several manufacturers will provide their client with interoperability that will allow for future sourcing options. They are disappointed when they discover that they have unknowingly created a situation where they must solely source from the initial supplier, eliminating any chance of competitive purchasing environment for the future. Tips for Selecting Smart Card Systems Here are a few tips to consider when selecting a contactless smart card provider to be used with your physical access control solution: Select a technology that offers the desired operational characteristics. For example, if maximum read range is a design consideration, make sure to select a technology that provides the desired read range (e.g. ISO 15693 vs. 14443). Chart 2. Sizing for biometric applications. Biometrics Technology Type Hand-scan Retina-scan Finger-scan Iris-scan Facial-scan Signature-scan Voice-scan 10 Advancing Information Transport Systems www.bicsi.org Sample Template Size 9 Bytes 96 Bytes 250 Bytes 512 Bytes 1,300 Bytes 1,500 Bytes 2,000 вЂ“ 10K Bytes FIBER Leviton makes it easy. Pre-terminated or п¬Ѓeld-terminated. Data center or enterprise. Connectors, enclosures or jumpers. Leviton has the п¬Ѓber products you need. From FastCAMв„ў, prepolished connectors to custom-conп¬Ѓgured, preterminated trunks, harnesses, enclosures and more, we make being connected easier. FIBER For more information call, 800.922.6229 or visit www.levitonvoicedata.com/п¬Ѓber. FIELD-TERMINATED SOLUTIONS PRE-TERMINATED SOLUTIONS FastCAM, FastCure and ThreadLock connectors Pre-Terminated Fiber Solutions Enclosures and adaptor panels MTP modules and panels Fiber jumpers Trunks and harnesses levitonvoicedata.com :: 800.922.6229 :: FAX 425.483.5270 ISO 9001:2000 registered quality manufacturer :: В© 2006 Leviton Manufacturing Co., Inc Select a technology that is deployed across a comprehensive product line. Ensure that your provider offers a full product line, including multiple form factors, multiple mounting options, keypad options, long range options, and multiple technology units. Select a product family that is available from multiple sources. History has shown that card and reader selection often outlives the access system selection. Also, vendor relationships can change unexpectedly. Therefore it is good business to select a product from a manufacturer with a wide and diverse distribution channel to ensure compatible products can be purchased from multiple alternate sources if necessary. For businesses that operate globally, ensuring the distribution channel operates globally should be considered. Ensure selection of a contactless smart card with sufficient memory size and secure application areas to accommodate data for other future applications. Understand how your customer may potentially benefit from a smart card in the future. Make sure the card you select has sufficient room to accommodate not only todayвЂ™s data, but also has room for the data that may be loaded on the card in the future. A good example is biometrics. Depending upon the biometrics technology selected, the size of the 12 Advancing Information Transport Systems www.bicsi.org biometric data template varies greatly. Chart 2 shows rough-order-of-magnitude biometric template sizes: When using the card for other applications beyond access control, select a technology that is utilized by a comprehensive list of application providers. In order to gain maximum value from the contactless smart card investment, it is important to make sure that a wide range of application providers uses the technology selected. Ask your contactless smart card provider for a list of approved application providers that utilize their technology. Reading the CSN (Card Serial Number) is not an effective identifier for access control. Read the fine print. Some smart card products merely read the CSN as the card identifying data. The CSN is a unique number programmed into each chip at the point of manufacture. It is intended as an ISO mandated anti-collision element to identify data coming from multiple cards being presented simultaneously to a single reader. Unlike the data stored in the memory of a smart card, the programmer has no control over the length or format of the CSN. More importantly, there is no security associated with the CSN. Any ISO compliant reader can read the CSN since it is not secured by a key or other security feature. Reading the CSN as the card identifier does not leverage any of the benefits provided by smart cards. The data stored in memory should be secured with a key. As discussed earlier, data locations within the contactless smart card chip are secured with a key. The key is like a password that defines access privileges for the protected data area. If multiple applications are storing data in individual memory locations, each location should be secured with a unique key to prevent intentional or accidental access or corruption of data. Some providers leave keys in a default condition, exposing the programmed data to tampering. A properly provisioned smart card makes responsible use of the inherent security features offered by the contactless smart card technology. Give your customers using legacy technologies multiple options to migrate to contactless smart card technology. Be sure to select a provider that offers maximum flexibility for migrating from legacy technologies. Multi-technology readers provide the capability to read cards from both legacy technologies (e.g., 125 kHz Prox) and new contactless smart cards. These units are valuable migration tools for clients with large legacy card populations, allowing clients to maximize their existing card investment and to replace cards over time. Multiple technology cards employ a mixture of technologies into a single card, allowing them to be read in legacy technology readers as well as new contactless smart card readers. Multiple technology cards can include Wiegand, 125 kHz Prox, magnetic stripe, bar code, contactless smart card and contact smart cards. Having both options (multi-tech readers and multi-tech cards) offers the maximum options to help make the migration process as smooth as possible. Conclusion As with other convergence technologies, smart cards provide users with value beyond the role of a secure physical access control technology. Organizations can also benefit from the increasing selection of non-security applications enabled by this technology: manufacturing control, cashless vending, point-of-sale, copy and print management, and event management, to name a few. This increased value comes at a very reasonable price, comparable to that of the limited 125 kHz proximity products. However, this increased value can only be realized if designers and integrators properly select and deploy smart card products that meet the anticipated needs of their customers. As the market responds to the increasing demand for smart cards, they must also begin to identify the issues that affect their selection of the best products to incorporate into their designed solutions. This takes an understanding of smart card technology fundamentals beyond the sometimes vague information contained on sales brochures. The flexibility and capabilities afforded by this technology can create a real danger of painting your cus- tomer into a corner if cards and card readers are not selected, provisioned and deployed properly. Any choice of cards and readers should provide customers with a wide selection of interoperable sourcing options for the future, too. To augment selection criteria, industry professionals are looking beyond the technical specifications toward the issues surrounding the business of smart cards. Sourcing options, interoperability, and after-sales service and support are becoming more important than ever. System design and integration professionals who embrace smart cards and the diversity of smart card applications are able to differentiate their company by distributing the value of the customerвЂ™s smart card investment across other areas of the organization. . Mark C. Peterson Mark Peterson is director, intelligent technology design resource group, for HID Global, a leading manufacturer in the access control industry. For more information, contact Mark at +1 303.453.4006 or firstname.lastname@example.org. Deployment & Rollout Support Services When you need the bestвЂ”hire the best! Hire a professional support organization for your national, regional or local deploymentsвЂ”a professional support team recognized by Bicsi as one of the world's finest! Look to Vision Technologies for your professional project management, ITS design, installation and support services. With Vision Technologies, one of only 21 Bicsi Prestige Platinum contractors worldwide, you are assured of consistent quality, on time delivery and adherence to your budget. We have decades of experience performing as the вЂњCompany behind the CompanyвЂќ, and we recognize that we only succeed when you succeed. When you partner with Vision, our commitment to 100% Customer Satisfaction is your assurance that your project will be delivered to your satisfaction. Vision Technologies provides: Certified Installers for: ; Nationwide e Coverage e ; Data a Centerr Design/Build/Supportt ; 11 1 RCDDss ; 12 2 TPMss ; 5 PMPss ; Bicsii Certified d Trainingg Centerr ; Bicsii Certified d Technicianss ; Bicsii Certified d Installerss (410) 424-2183 email@example.com www.visiontech.biz A Service Disabled Veteran Owned Small Business GSA Contract Holder (GS-35F-0581R) BICSINEWS January/February 2007 13 Feature Building a Redundant and Resilient College Network Best practices design ensures the network will easily adapt to changing technologies. BY RICHARD JOHNSTON Few industries have been transformed by computers and networking as much as higher education. Spanning from years ago when students stood in line to collect punch cards to register for courses to todayвЂ™s Internet accessible course content and potential to earn degrees without setting foot on a campus, the network has grown into a vital component for all colleges and universities. This article reviews the best practices and processes undertaken by Suffolk County Community College to implement an enterprise-wide network to support the institution for next 10 to 20 years. 14 Advancing Information Transport Systems www.bicsi.org Suffolk County Community College is located on Long Island, New York with a network that spans 80 miles from the western border of Suffolk county to Montauk on the southern fork. The college has three campusesвЂ”the Grant Campus in Brentwood, the Ammerman Campus in Selden, and the East Campus in RiverheadвЂ”as well as several satellite sites that offer courses and programs within local communities. More than 24,000 students and 2,000 faculty and staff use the network. Classes are offered seven days a week with start times as early as 6 a.m. and end times as late as 10:30 p.m. College programs range from traditional liberal arts to special programs such as automotive engineering and veterinary sciences. The initial challenge revolved around a patchwork of many independent and incompatible networks, with devices operating over DECNet, Novell, AppleTalk, NetBIOS and TCP/IP. Cabling was varied and there was no governing master plan or guidelines on how to expand the network. It was through the process of documenting what existed that naturally led to a planning document to consolidate the network and repair or replace the infrastructure. In this early phase, lack of documentation was a frustration that delayed understanding of the existing network. By researching how to communicate best practices on building infrastructure, the most successful implementations followed a basic concept of a layered approach. After all, the network protocols finding acceptance in the marketplace had layers, as well as the methodology for interconnecting devices. The capabilities of the telecommunications services were layered. Even the organization of the collegeвЂ”students, faculty and administratorsвЂ”was presented in layers. Therefore, the approach to building the network was to be accomplished in layers. By constructing layers within the infrastructure and building upon the supporting parts of each, a full stack could be completed over a period of time while maintaining the operation of current systems. Today, the layered view of the world continues across the college in staff responsibilities, project evaluations and scheduling priorities. Building the Network Building a large-scale network is a never-ending task at the college because limited staffing must be balanced against long days of classroom schedules. This creates a cyclic problemвЂ”by the time an upgrade plan is finished, new technology has been introduced and the installed components will have a shorter operational life. To get ahead of this process, larger projects are done with larger staffs. This requires a temporary staff that is knowledgeable of the project and the goals. Suffolk acquired additional staff by contracting with cabling installers, equipment manufacturers and VARs and was able to tap extensively into their expertise. Since the college is part of the county government, regulations require large projects to follow an RFP process. Two factors of this process assisted the college in achieving its goals: вЂў The RFP must have exact descriptions of the environment, technical details, scheduling, and the desired goals (work, equipment, or talent). Best Practices Employed by Suffolk County Community College Design twice, implement once вЂў Use a test bed to verify anticipated outcome Document the network based upon layers вЂў Cable IDs (fiber strands or pair numbers), jacks and locations вЂў Circuit IDs, device ports and parameters вЂў IP addresses and subnet Document your standards and practices for others to follow вЂў Cabling and wiring conventions вЂў Network IP address allocations and VLAN usage вЂў Device naming or numbering conventions Have a multiyear plan вЂў Statement of goals for short and long term вЂў Include current network structure вЂў List of facilities locations (MDF, IDF, electrical closets) вЂў Project descriptions, schedules and equipment lists вЂў Long term project information Use temporary staff to augment permanent staff вЂў Use expertise from contractors, resellers, and manufacturers вЂў Maintain relationships to eliminate learning curve вЂў Explain future plans and schedules вЂў Require certifications Leverage other projects to build infrastructure вЂў Participate in renovations and construction projects вЂў Include long range goals in plans вЂў Build for the future using todayвЂ™s dollars Use an RFP approach even without bid вЂў вЂў вЂў вЂў The RFP process requires exact specifications Define equipment and statement of work Review schedule prior to a commitment Ensure better understanding of project Use other best practices and standards вЂў Reduces workload вЂў You donвЂ™t have to reinvent the wheel or be a trailblazer вЂў Pick and choose practices which match your environment вЂў Leverage on the research done by others BICSINEWS January/February 2007 15 вЂў Multiple firms compete and get reviewed, which leads to a winning firm that has the capabilities to perform the work or deliver the equipment. The college has been successful with this process and has worked with several firms that have continued the business relationship long after the initial contract was complete. One of the first projects addressed growth of the network and the use of PCs within the college. The goal of the Universal Connectivity Project was to provide PCs and networking for each classroom, faculty and staff member. This allowed rapid construction of the access layer of the network. New telecommunications rooms (TRs) were constructed to terminate cabling and install the hubs. The вЂњspace warsвЂќ on gaining proper square footage and location for TRs was a study in diplomacy, but the result was a dramatic increment in the scale of the network. Installation of a large number of cables, patch panels, racks, and hubs required several teams to build the TRs, based on a standard that would adapt to individual circumstances. To assist in this process, the first draft of the collegeвЂ™s Wiring and Cabling Standard was instituted. This documented the cable requirements for classroom, computer lab, lecture halls, faculty office, clerical spaces and administrative offices. The standard addresses the types of cables and the acceptable products to be used. This document continues to be updated for new technologies, such as wireless, VoIP, and new indoor and outdoor spaces. With addition of so many additional devices in a single project and with the collegeвЂ™s continued growth with the purchase of new equipment every year, the network was growing dramatically. Bottlenecks within the interbuilding links and greater demand for Internet access were causing issues. Resolving these problems required two projects to jump the support level of networking services within the college well beyond its current needs. 16 Advancing Information Transport Systems www.bicsi.org The first was a WAN upgrade project, which replaced core switches and routers. The second project was a LAN upgrade project, which replaced the distribution layer of network equipment and funded the installation of an all optical fiber network to every buildingвЂ™s main distribution frame (MDF) and to each intermediate distribution frame (IDF). These projects were successful because of well-trained contractors and well-defined plans. In rebuilding the distribution layer, the college installed additional conduits and manholes to provide new paths to existing buildings and to create the interconnect points for new buildings. The use of a cabling company with a BICSI Registered Communications Distribution DesignerВ® (RCDDВ®) with an Outside Plant (OSP) Specialty provided the expertise to design an infrastructure with a projected service life of more than 20 years. The continued business relationship with the cabling company allows the college to plan several years ahead and have the resources available when needed. The use of an RCDD ensures that implementations are performed to specification and that short- and long-term goals are understood and planned. During the LAN upgrade project, reliability and survivability of the TRs was taken into account. Each MDF and IDF had its electrical power sourced on emergency circuits with generator backup. To offer equipment protection, UPS units were installed as well as network and temperature/humidity sensors that communicate back to a central management device that monitors and pages staff if faults or environmental violations occur. This allows 75 TRs to be monitored 24/7 with minimal staff support. Along with network growth within the collegeвЂ™s existing buildings, the college constructed new buildings for new instructional areas. The largest of these buildings was the health, sports and education facility on the Grant campus. This is a large athletic and academic building constructed as seven attached buildings with two three-floor academic wings, a field house with a 200 m track and bleacher seating for 3,000, a health club with pool, and the countyвЂ™s police academy. The complex is so large that it is designed with five MDF wire closets (one per wing) interconnected with singlemode and multimode optical fiber cable. In fact, every classroom has a hybrid cable of two singlemode and four multimode strands housed in a metal BX-style cable that terminates in the lectern. This allows streaming video or Internetbased presentations into each classroom. More than 120,000 feet of this hybrid cable is used to interconnect the academic and lecture spaces, including optical fiber outlets embedded alongside the main basketball court for video and presentations. Fourteen access points provide wireless network coverage in the field house, which is used for athletic events, conventions and shows. The most recent upgrade to the network and the most complex design change was the replacement of the college telephone system with 1,500 VoIP digital handsets and 800 analog gateway ports. The old telephone system had five PBX nodes and supported multiple departmental PBX systems. The new system has redundant servers for each campus and failover to off-campus servers. Use of both a VAR with prior experience with the collegeвЂ™s network and direct manufacturer involvement greatly assisted in making the change. Seven months of planning and network modifications prepared the way for a fast implementation. The equipment was delivered in mid-February and cutover was on April 10. The VAR was able to provide 20 staff to assist in delivery, unpacking, installation and testing of 1,200 telephones within five days. On the day of cutover, nine T1 circuits were moved and 650 analog lines were re-circuited. After performance and acceptance testing were completed, the system was successfully turned over to the college. Of the more important features incorporated into the new telephone system was 911 support. The new 911 Take Control of Your Projects with IntelliBid Estimating Software Voice вЂў Data вЂў Copper вЂў Fiber Surveillance вЂў CCTV вЂў Card Access Fire Alarm вЂў Audio вЂў Video Nurse Call вЂў Public Access Building Automation вЂњHelping the Electrical and Cabling Industries Take OffвЂќ ...since 1989 18 ConEst Software Systems В® 800 . 662 . 7687 www.conest.com Advancing Information Transport Systems www.bicsi.org server reports the exact office locationвЂ”wing, floor, building, and addressвЂ”to local authorities, instead of merely showing the listed address of the college. Providing this information decreases response time in an emergency. Before the new system was implemented, 911 would direct the emergency equipment to stop at the campus security office to ask where to go. To have the 911 system operate correctly, exact location of handsets must be documented in a central database. By labeling each outlet and jack per TIA/EIA 606a standards, the information was easily collected and the database created. Normally, documentation is improperly done or undone because of cost cutting. Now, it is an integral requirement that can save lives. What the Network Can Now Do The projects that created the college network have provided a robust and redundant network that self-heals from service outages and maintains campus survivability. The most critical service that the network provides is telephone because this service must operate 24/7 with five nines reliability. Therefore, network reconfiguration or modification requires advance notice to a department, an entire building or possibly a campus prior to performing any task. The core network is designed with redundant paths between campuses. The telephone system uses the inter-campus optical fiber links for normal extension-toextension traffic. If these links fail, then the PSTN trunks are used by adding the missing digits. If the PSTN trunks fail, then local outbound calls are routed to another campus and incoming calls are rerouted to another campus, upon notification of the local PSTN. The next most critical service is for the servers that provide e-mail and network-based applications as well as other servers in the SAN that are needed for normal operations. The college is moving the MicrosoftВ® My Documents folder for every administrator and faculty member from the local PC drive onto the SAN. As a result, the network is required for PC users to perform office clerical functions. In addition, administrative applications are moving from mainframe-based applications to database servers that are outsourced. The typical functions of the college, such as registration, bill payment and grades, are now using network connections for data access. A loss of network function has the effect of shutting these departments down. Because a network failure would result in cancellations of class sessions, there are also dedicated academic servers for use within the college and for students off campus. The Internet is now being used by the college to provide connectivity to services and content for students and faculty off campus and in the classroom. Inbound Data Center Myth Busters Myth To achieve 20 kW of cooling you must use liquid or active cooling systems in or near your cabinet. Fact You can achieve 2-20+ kW of cooling without resorting to liquid or active cooling systems by simply reclaiming control of the cold air in your data center. Does cooling your data center seem like a mystery? As equipment power densities continue to increase in the data center, thermal management has become a major operational and facilities management challenge. Chatsworth Products, Inc. (CPI) SM Passive Cooling Solutions offer an innovative technique that allows you to control the flow of air throughout your cabinet. CPI Passive CoolingSM Solutions offer: вЂў Flexibility - Uncomplicated moves, adds and changes - Configurable to meet specific needs вЂў Scalability - Adaptable for increasing power density requirements - Achieves 2-20+ kW of cooling per cabinet вЂў Tier IV Capability - Advanced thermal control with zero point of failure - Vertical Exhaust Duct directs hot air out of the cabinet and away from equipment вЂў Minimize Total Cost of Ownership - Maximizes CRAC effectiveness - Decreases ongoing maintenance costs - Reduces risks and costs associated with supplemental liquid and active cooling systems Visit CPI booth at the 2007 BICSI Winter Conference and meet Dr. D. Bunk, CPIвЂ™s Cooling Expert who will help you clarify fact from fiction in achieving the ultimate data center cooling strategy. Ask Typical server cabinet without Typical server cabinet with CPI Passive Cooling. Hot exhaust CPI Passive Cooling Solutions. air is shown recycling over the top of Hot exhaust air is isolated from the cabinet and is pulled back into the room, therefore intake temper- equipment at over 100ВєF (38ВєC). atures stay within optimal ranges and equipment is protected. The TeraFrameв„ў Cabinet System offers CPI Passive Cooling Solutions to achieve 2-20+ kW per cabinet of cooling without having to use liquid or active cooling systems. Customize your TeraFrame using CPIвЂ™s Product Configurator at www.chatsworth.com/configurator, or try one of our bundled solutions designed to meet the most common data center needs. Dr. D.Bunk www.chatsworth.com or firstname.lastname@example.org 800-834-4969 and outbound traffic requirements are rising every semester and the need for redundancy and resiliency to maintain access is a must-have feature. Students opting for distance learning environments will further increase demand for the services. One of the newer tasks for the network is video distribution. Each campus has two sets of distance learning equipment that consists of codecs, microphones, speakers and cameras for providing PTP or point-to-multipoint distribution. One set on each campus is in a fixed configuration in a distance-learning classroom that allows students to attend a class without traveling to another campus. The other set is portable and can be set up for special events that are broadcasted to other classrooms anywhere in the college. A typical application of this technology is a speaker in the theater who can be viewed across the college in any classroom. The network also supports infrastructure automation, such as the HVAC systems, security cameras, door access systems and, in the future, paging systems. These operate continuously and are accessible to authorized users from anywhere on the network. These applications have shifted the importance of the network from a casual utility to a mission-critical service that is integrated into every facet of the collegeвЂ™s operation. Of the lesser-known functions of the college is participation in natural disasters or health related emergencies. This requires that the college provide space for evacuated residents or for emergency operations. To assist in providing services during these events, the network has capacity and components configured to allow them to be shifted from academic to emergency services functions. Summary The evolution of the Suffolk County Community College network has been accomplished by strict adherence to best practices design and standards, high performance equipment, documentation, and with close partnerships with cabling companies, equipment manufacturers, and integrators. The abilities of the network will continue to evolve as the needs of the college change and as technology moves forward. Keeping up with the growing network requires networking professionals to continually enhance their skills and learn about the new technologies to ensure that todayвЂ™s decisions will provide a growth path to the future. . Richard Johnston, RCDD Richard Johnston is director of network and telecommunications for Suffolk County Community College on Long Island, NY. Richard can be reached at +1 631.451.4190 or email@example.com. 2007 BICSI European Conference 20 Advancing Information Transport Systems www.bicsi.org N 00 7 2 E E N IN L B D U N D LA E IR JU Discover the countless emerging technologies and innovative ideas that are directing the future of the ITS industry. Experience the festive culture, rich history and breathtaking natural beauty that can only be Dublin, Ireland. 1 8 -2 0 J U Citywest Hotel, Conference, Leisure & Golf Resort, Dublin, Ireland TEST LAB REAL WORLD THE NEW NEXTLAN 10GC В® BREAKTHROUGH PERFORMANCE, EXACTLY WHERE YOU NEED IT To engineer NextLAN 10GC, we used the ultimate test lab: Reality. We focused our design efforts on making a system that will provide peak performance in a real-world environment where interference is uncontrolled and the cabling system needs to run at 10G speeds without error вЂ“ 100% of the time. The result? The п¬Ѓrst UTP cabling system that fully complies with the latest draft ANSI/TIA standard for 10 Gigabit Ethernet cabling requirements and includes a 4dB margin guarantee for Power Sum ACR. OTHER CABLING SYSTEMS ARE FINE IF YOU WORK IN A TEST LAB. LEVITON AND SUPERIOR ESSEX MADE SURE THAT NEXTLAN 10GC PERFORMS LIKE A DREAM IN REAL LIFE вЂ“ YOURS. Next Time, NextLAN. www.NextLANsystems.com Feature How to Work with the Authority Having Jurisdiction Document, seek permission and have records available. BY MIKE TOBIAS Inspectors today are burdened with technical issues and tremendous challenges when inspecting low voltage cabling. Many jurisdictions do not require a permit to be pulled by the information transport systems (ITS) installer and have no idea that a cabling project is even under way. Invariably, it is when the inspector, the authority having jurisdiction (AHJ), comes to inspect a building for the regulated crafts that they happen to catch problems associated with the ITS wiring and infrastructure. Most inspectors have no formal training in high speed network cabling, especially with regard to what makes it function and perform. The AHJ is therefore typically not interested if the network runs at its advertised speed. What does concern the AHJ is placement of cables through fire rated walls/barriers and code issues such as grounding and bonding the system. When violations are present, the AHJ is required to take corrective action. ThatвЂ™s their job. It is important to remember that the AHJ is a person just like you and meвЂ”burdened with tremendous responsibility and held accountable for their performance. What Does вЂњQualified PersonвЂќ Mean? When an AHJ finds a problem with an ITS installation, the first item of interest is the installerвЂ™s qualifications, which in itself can be a rather vague proposition. Some installers may show evidence of training and competence, such as BICSIвЂ™s ITS Installer designation, but this isnвЂ™t a code requirement. The current definition of installer qualifications in the 2005 National Electrical CodeВ® (NECВ®) states, вЂњOne who has skills and knowledge related to the construction and operation of the electrical equipment and installations and 22 Advancing Information Transport Systems www.bicsi.org has received safety training on the hazards involved.вЂќ Apparently, there is no requirement that the qualified person is required to have any formal training except for minimum safety training requirements. Therefore, most inspectors judge the network cable installerвЂ™s qualifications by the workmanship seen on the job. As a result, some AHJвЂ™s require a written document to substantiate qualifications if the level of quality is in question or if the AHJ is not familiar with a new concept or system recently introduced. The NECВ® definition of a qualified person does not currently require documentation of training, but a lot of inspectors consider it to be common sense to check someoneвЂ™s credentials if their qualifications are in question. If you carry a certification or designation, there should be no questioning that credential. This is why you attend training and strive to be competent. Perhaps an improved definition of вЂњqualified personвЂќ would be as follows: вЂњqualifications to be true by demonstration or evidence.вЂќ This would prompt the AHJ to ask for and verify credentials, which happens quite often. Therefore, if an installer is trained and is not performing work correctly, the inspector may or may not accept his credentials. In fact, most inspectors will let you know if your вЂњcertified installerвЂќ is not doing the job that he or she was trained to do. It is not unusual for a manufacturer to be called by an AHJ when the work of a trained installer is in question. In these cases, the AHJ seeks to correct the problem and ensure the installer is retrained. If you acquire formal training, use it. If you have no formal training and expect to get by without it, your days on the job could be numbered. If you have formal training, be prepared to furnish verifiable proof of your CompetitorвЂ™s Category 6 Cool technology. Category 6 with AirESВ® When it comes to cable, smaller is best. ThatвЂ™s what you get with copper cable made with AirESВ® technologyвЂ”exclusively from ADC. Air is combined with solid beams of FEP for individual conductor insulation. The result is cable that is smaller, lighter and more crush resistant. In fact, AirES cable is 32% smaller than typical Category 6 cable. What does this mean for you? вЂў Improved data center coolingвЂ”smaller cable enhances airп¬‚ow and improves reliability and uptime вЂў Reduced installation costsвЂ”smaller, lighter cable means pulling more cable at the same time вЂў Decreased capital expensesвЂ” smaller cable improves п¬Ѓll rates in cable trays, conduit and raceways For cooler data centers and maximum system uptime, insist upon cable made with exclusive ADC AirES technology. To help you choose the right cable for your application, contact us today for your complimentary interactive Cable Selection Guide. ItвЂ™s another ADC exclusive. 1-800-366-3891 or +1-952-938-8080 вЂў www.adc.com/truenet See us at BICSI Winter вЂ“ Booth 411 Angled Copper Patch Panels В©2007 ADC Telecommunications, Inc. All rights reserved. Fiber Patch Panels CopperTenВ® Cable Angled MPO Cassettes FiberGuideВ® Raceway qualifications to the AHJ if asked. It is also smart to include your credentials any time you are making submittals to the AHJ. Who is the AHJ? The AHJ comes in the form of many different people. Typical AHJвЂ™s are the city and county electrical and structural inspectors. There are also the state fire marshals and federal inspectors who inspect health care facilities funded by Medicare or Medicaid. Their authority is never questioned. Installers should read the fine print in the local code book detailing exactly who the AHJ may be. For example, in the definitions section of the current version of NECВ®, there is a footnote on AHJ that catches most people by surprise: The phrase вЂњAuthority Having JurisdictionвЂќ is used in National Fire Protection Association (NFPA) documents in a broad manner, since jurisdictions and approval agencies vary, as do their responsibilities. Where public safety is primary, the AHJ may be a federal, state, local or other regional department or individual such as a fire chief, fire marshal, chief of a fire prevention bureau, labor department, health department, building official, electrical inspector, or others having statutory authority. For insurance purposes, an insurance inspection department, rating bureau, or other insurance company representative may be the AHJ. In many circumstances, the property owner or a designated agent assumes the role of the AHJ; at government installations, the commanding officer or department official may be the AHJ. If the person is in charge, you have no choice except to answer to them. The AHJ is ultimately responsible for safety of people in the building and if there is ever a problem, the AHJ is held accountable. It is no wonder that many inspectors seem difficult and some AHJвЂ™s find вЂњunqualifiedвЂќ contractors to be annoying. Strategies for Working with the AHJ Where you will work with the same inspectors over multiple projects, it is especially important to create a comfort zone for the AHJ. Providing AHJвЂ™s with what they need results in smoother inspectionsвЂ”and lower costsвЂ”on every project. They all want the same thing, so why not give it to them up front? Use a pre-approval process. Create or download an AHJ consideration form, which is basically a вЂњrequest for considerationвЂќ form that details location and time of installation, methods and solutions used for firestop, grounding or other installed components that matter to the AHJ. Send this along with other submittal documents. What you might experience is an inspector who respects your ability to convey your intentions on the work to the point that they donвЂ™t have to inspect. In fact, inspectors are typically shocked by a contractor who even mentions firestop, much less contacting them about the subject. This proactive approach usually impresses AHJs. How NOT to Treat the AHJ ! A man in a three-piece suit carrying a briefcase showed up on a large retrofit jobsite where the installer was removing abandoned cable and installing new network cables. The man had no hardhat and or steel-toed boots. During the wreck-out, the man began to look over the shoulders of the installers and was inquiring about how the contractor was to seal the fire-rated barriers. He introduced himself as being from the insurance company and performing a risk assessment. He was not in uniform and did not have a badge, so the installer quickly dismissed him and escorted him from the jobsite without responding to his request for information. A week later the same insurance man showed up with the state fire marshal, who immediately red-tagged the doors and evacuated the building on the spot. The insurance man explained to the installer that he had kicked the AHJ off the job a week earlier and that the contractor should read the definition of AHJ in the NECВ®. The fire marshal went on to explain that once the jobsite met the concerns of the insurance agent, the fire marshal would be back to perform an inspection on behalf of the state. This is not a good thingвЂ”always be courteous and helpful to who at first may be perceived as вЂњstangersвЂќ on the jobsite. 24 Advancing Information Transport Systems www.bicsi.org In many cases, after an AHJ inspects your work several times, their confidence in your work is such that they ask you to stop seeking permission. They know your work and your commitment, you become automatically preapproved, and your work becomes one less item for the busy AHJ to deal with. Take photos. An organized set of labeled digital photos with penetrations alphanumerically identified may result in review over a cup of coffee rather than having to pull the ladder out and carry it around the building. Mike Tobias Mike Tobias is CEO of Unique Firestop Products, a manufacturer of fire-rated barriers for commercial applications in Robertsdale, AL. Mike can be reached at 877.960.5018 or mtobias@ uniquefirestop.com. Label plans. Assign an alphanumeric identification to each inspection item and have plans on the table. Once the first floor is reviewed by the AHJ, a simple review of the detailed plans may not require inspection of other floors with like solutions. Conclusion It is important to know who qualifies as the AHJ, if for nothing else to avoid alienating the person who needs to approve your project. The AHJ could be a county inspector or the building ownerвЂ™s secretary, so it is important not to make assumptions about who is on the jobsite. Most inspectors are in the field during the day so the best time to reach them by phone is early morning hours, such as between 7 to 8 a.m. The receptionist at the state or local government office can usually tell you which official covers your jurisdiction. Submit pre-approval consideration forms along with documentation and submittals. Acquire manufacturer training and put it to use. Credentials are a good thing to have, either from manufacturers or professional associations such as BICSI. Attend as many courses and classes as you can and you will soon be accustomed to seeing the AHJ smile at you and move on to another jobsite. . WhatвЂ™s at the core of your fiber? Chances are you donвЂ™t know. Some fiber manufacturers donвЂ™t specify bandwidth in the critical center region of the fiber. But when you select OFSвЂ™ LaserWaveВ® OM3 fiber, you get outstanding performance right down to the core. LaserWave fiber delivers DMD specified in the 0 вЂ“ 5 micron range and up to twice the bandwidth for lasers that launch power in the fiberвЂ™s center. Enjoy fast, reliable transmission and easier connectivity. To learn more, ask your cabler about OFS or visit ofsoptics.com/fiber. BICSINEWS January/February 2007 25 Feature The Wi-Fi Path Loss Equation and Antenna Specifications Making sense of manufacturer specifications. BY JOE BARDWELL Wi-Fi is the designation for a relatively broad family of wireless devices that communicate in accordance with the standards set by the IEEE 802.11 committee and a variety of working groups. The antenna that is used with a Wi-Fi radio (e.g., access point, repeater, mesh router, bridge, or client device) makes a big difference when it comes to the radioвЂ™s ability to transmit and receive. Understanding the choices available and their strengths and weaknesses requires some background. This article provides information that can be applied to selection of indoor and outdoor antennas for Wi-Fi systems. Over the past year, the type of Wi-Fi devices found in the marketplace has dramatically evolved from the basic notebook computer used to check e-mail and surf the Web, to multi-mode cell phones with Wi-Fi wireless VoIP, wireless security systems and location tracking, backhaul for radio frequency identification (RFID) product tag readers, licensed public safety applications, and much more. As the sophistication and capabilities of the applications and devices that communicate over Wi-Fi networks has increased, so has the need for best practice designs and equipment specifications. While a consumergrade access point may provide minimal levels of service for simple e-mail and Web access, only commercial-grade equipment, coupled with proper RF engineering in the design, will support the levels of service that will be required over the course of 2007 and beyond. The Antenna as Part of a System A Wi-Fi system design consists of a number of access points spread across the indoor or outdoor coverage area. The design of the network determines where the access points will be installed. Requirements for a correct design are simple: 1. Transmitters must propagate signal energy that is powerful enough to propagate throughout the intended coverage area. 2 Receivers must be sensitive enough to recover the data bits out of the signal energy present in the installation environment. 3. The ratio of signal energy to background noise and interference must be large enough to allow the receiver to identify the desired transmission. 26 Advancing Information Transport Systems www.bicsi.org The requirements may be simple, but meeting them can be complex and confusing. While this article focuses on the first point, transmitted power, none of these points can stand completely alone. The power that must be radiated from a transmitter is required to meet the sensitivity requirements of the receiver. The signal-tonoise ratio (SNR) is a requirement specified by the radio manufacturer and is based on the capability of the receiverвЂ™s circuitry. In essence, receiver sensitivity and required SNR may be considered fixed values, varying only from one model of radio to the next. In addition, the maximum power output of the transmitter may also be considered a fixed value, limited by the manufacturer, often in compliance with legal requirements. The variable that remains, and the choice which must be made by the designer of a wireless network system, is the antenna to be used by the radio. We will discuss antenna selection on the basis of the underlying physics of wave propagation. Antenna Basics Selecting one antenna over another is always a matter of trade-off. The antenna is simply a radiating device that receives power from the access point and causes that power to propagate outwards as electromagnetic waves. An antenna designer can do many things to shape, direct and focus the propagating signal, but they cannot create more signal than was input into the antenna by the access point. In this lies the focus of the tradeoffs in antenna design. The design is based on the laws of physics of electromagnetic wave propagation and there is no free lunch in the physics department. Data bits are sent from a deviceвЂ™s operating system software to an 802.11 Wi-Fi chipset. The chipset and supporting circuitry modulates a carrier signal to represent bits using specific variations of the carrier. This modulated carrier is the electrical signal that is input into an antenna. The result is the propagation of an electromagnetic field that conveys the data bits in a known series of variations. There are three basic concepts that are the foundation for antenna specification: As Simple (and Quick) as 1 to 3 Get the cabinet you want, when you need it. Get the customized IT cabinet you N Reliable need in just one to three days with two N Flexible new quick-ship programs from Rittal. N FAST 1 Day Program Within 24 hours, we will ship the Rittal cabinets and accessories you need. Simply choose the networking or server cabinets and sidewalls that best meet your requirements. Select the fans, electrical components, cable management devices, hardware or other accessories for your application. 3 Day Program Choose your cabinet. Select your accessories. WeвЂ™ll assemble the complete unit to your desired conп¬Ѓguration. The ready-to-use unit will ship in just three days. When you receive it, simply load it and plug it in. No mussвЂ¦no fuss. Learn more about RittalXPress quick-ship programs at www.rittal-corp.com/rittalXpress/it.cfm. Rittal Corporation вЂ“ One Rittal Place вЂ“ Springп¬Ѓeld, Ohio 45504 USA Phone: 937.399.0500 вЂ“ Fax: 937.390.5599 вЂ“ E-mail: firstname.lastname@example.org вЂ“ www.rittal-it.com mW and dBm Defined The mW and dBm scales are both used to represent signal power. Conversion between the units involves a scientific calculator, but there are a number of rules of thumb that can be easily applied. To convert from mW to dBm: Calculate the base 10 logarithm of the mW value, and multiply the result by 10. dBm = log10(dBm) * 10 To convert from dBm to mW: Divide the dBm value by 10, then raise 10 to that exponential power. mW = 10^(dBm/10) Here are some rules of thumb to remember: вЂў 100 mW = 20 dBm (power consistent with commercialgrade access points) вЂў 1000 mW (1 watt) = 30 dBm вЂў 30 mW = 15 dBm (power consistent with many notebook computers) вЂў Adding 3 dBm results in doubling of the mW value (18 dBm = 60 mW, start with 30 mW = 15 dBm and double the mW because you added 3 dBm) вЂў Subtracting 3 dBm results in halving the mW value (17 dBm = 50 mW, start with 100 mW = 20 dBm and divide mW by 2 because you subtracted 3 dBm) 28 1. The isotropic radiator. 2. The inverse square law. 3. The decibel unit of measurement (dBm, dB, dBi). The Isotropic Radiator To begin considering how antennas work, imagine a single tiny point in the vacuum of outer space. Imagine that signal energy has somehow been input into the point without any wires or connections that would distort it and a resulting electromagnetic field is radiating outward. This field radiates out as a perfect sphere, with equal power at equal distance from the point, in all directions. This theoretical point source is called an isotropic radiator (from the Greek isos, meaning вЂњequalвЂќ and tropos meaning вЂњturnвЂќ). It produces a consistent, equal electromagnetic field in all three-dimensional directions. The Inverse Square Law The details of how the power that is applied to the antenna (from the access point radioвЂ™s antenna output) and how the energy ends up being propagated into space as electromagnetic waves is beyond the scope of this article. Nonetheless, it is important to realize that signal strength initially drops off quickly in the area very close to an antennaвЂ”roughly one to two wavelengths or five to 10 in for a 2.4 GHz 802.11b/g transmitter. After that, the expanding electromagnetic field decreases in strength in accordance with the inverse square law. This law of electromagnetic wave propagation holds that when the distance from the antenna doubles, the signal strength drops to 1/4 of its original value. If a measurement is made 20 ft away from an antenna, and another measurement is made 60 ft away from the antenna, the signal power decreases by a factor of nine because the distance is three times greaterвЂ”hence, the signal power is 1/9 of its original value. Power Represented as Milliwatts or dBm (dB Milliwatts) RF engineers represent signal power in a variety of ways. Two common representations encountered in 802.11 wireless LAN design are the milliwatt (mW) and the dBm. These, somewhat like miles-per-hour and kilometers-perhour, both represent identical quantities, simply using different numeric scales. The mW scale is linear and the dBm scale is logarithmic, as discussed in the mW and dBm sidebar on the left. A typical Wi-Fi access point has a maximum transmit power output (TPO) of 100 mW, which is the same as saying 20 dBm. A typical client device may only have a 30 mW (14 dBm) power output. A typical Wi-Fi device may be able to receive signals that have propagated outwards and fallen from 100 mW to a low power level of 0.000000000316 mW. This is why the dBm scale is helpful. This mW power level is represented as -95 dBm, where the negative exponent indicates the value is a fraction less than 1. The term Received Signal Strength Indicator (RSSI) is often used to refer to this receiver sensitivity value. It is common to see specifications of transmitter power output represented as mW, such as 100 mW TPO. However, receiver sensitivity values are always shown as a logarithmic, dBm value, such as -95 dBm RSSI. Advancing Information Transport Systems www.bicsi.org Figure 2. Coverage Model Showing Elevation Plane Signal Power at Various Angles Measured at a Fixed Distance Figure 1. The Rubber Duck with a Surrounding Electromagnetic Field The Dipole Antenna There is no perfect isotropic radiator in the real world. The simplest antenna is a pair of radiating elements typically encased in plastic or fiberglass called a dipole antenna, or more commonly known as a rubber duck. Early versions of this antenna were flexible and covered in rubber, hence the nickname. Like a bar magnet with lines of force circling outwards from the north and south poles, electromagnetic waves propagate horizontally outwards from a vertically oriented dipole antenna with very little signal energy present straight out the top and bottom of the antenna, shown in Figure 1. The radiation pattern coming out of a dipole antenna, following the electromagnetic lines of force, does not radiate in a perfectly spherical pattern. Rather, the sphere is flattened to form a shape that might be described as a doughnut. More correctly, this shape is called a toroidal pattern. therefore, adds 2.15 dB to the TPO. Therefore, the 18 dBm transmitter has an effective power of 20.15 dBm. When TPO and antenna gain are added, the resulting value is called the Equivalent Isotropic Radiated Power (EIRP.) Occasionally you may see gain represented as dBd (dB relative to dipole). The dBd metric tells you how much better, in the real world, the measured antenna is relative to the simplest possible antenna (the dipole). An antenna with a 5 dBi gain would be rated with a 2.85 dBd gain Antenna Gain Consider a situation in which a transmitter has an 18 dBm TPO. As such, 18 dBm of power is being input into the dipole antenna. The output power, however, does not radiate equally in all directions. Consequently, the power density is not equal in all directions. The 18 dBm has to go somewhere, and it doesnвЂ™t go out equally in all directions, which makes the effective power density on the horizontal plane (of the vertical antenna) greater than 18 dBm. This is because very little power goes out the ends of the dipole. The power is concentrated to the sides. This effect is called antenna gain. It is the degree to which the signal power is concentrated more in some directions than in others. One way to represent gain is as the ratio of the actual signal power density and that which would be present if the antenna were a perfect isotropic radiator. This logarithmic ratio is called dB relative to isotropic, dBi. A simple dipole antenna has a gain of 2.15 dBi and, BICSINEWS January/February 2007 29 Figure 4. Dipole Elevation Graph вЂ“ Detail View Figure 3. Typical Dipole Elevation Pattern Graph (because 2.15 + 2.85 = 5). Most manufacturers donвЂ™t use dBd metrics because, all other things being equal, the numbers are smaller than the dBi values used by their competitors and the marketplace would likely be confused. Using RF CAD modeling and simulation software, a coverage model showing signal power was developed for a vertical 2.15 dBi antenna with a 30 mW TPO. See Figure 2. The display is a side view, as seen by someone standing on the ground, looking at the antenna that is pointing straight up in the middle. This coverage model represents a distance of left-to-right horizontal distance of 7500 feet. Signal power measurements for three different angles are shown. The term elevation plane is used to refer to a side view. A top-down view is called the azimuth plane. In the elevation graph, red and yellow hues are вЂњhotвЂќ (higher power) and вЂњcoolerвЂќ (lower power) signal levels are represented by varying blue hues. Notice in the elevation plane coverage model that the maximum power measured is -85 dBm. At another angle the power is 5 dB less, or -90 dBm, and another measurement was 10 dB less at -95 dBm. This relationship between angle and power reduction is consistent no matter how far away a measurement is made. A special graph, called an antenna pattern graph, is provided by manufacturers to show how their antenna will operate. The Antenna Pattern Graph Manufacturers and distributors provide antenna pattern graphs to show the performance of their antennas. There are two graphs typically presented: the azimuth graph showing the top-down view and the elevation graph showing the side view. Pattern graphs are presented on a polar coordinate plane marked from 0- to 360-degrees relative to the antenna (in the middle.) ItвЂ™s important to confirm exactly how the manufacturer has oriented their antenna for 30 Advancing Information Transport Systems www.bicsi.org measurement. For example, an antenna intended for ceiling mounting is oriented 90-degrees to one thatвЂ™s intended for wall mounting. Interpreting the azimuth and elevation pattern graphs depends on knowing what was intended by the manufacturer. A typical mast mount dipole antenna is assumed to be mounted vertically, with the base of the antenna towards the bottom. The elevation pattern graph for a typical dipole is presented in Figure 3. Notice that the circumference is marked from 0 to 360 degrees and the horizontal line across the middle is marked from 5 dB to 30 dB, going from the outside to the center (note that there is no вЂњ5вЂќ for the +5 dB gain point to the right of the вЂњ0вЂќ point.) A detailed view of the graphвЂ™s markings is shown in Figure 4 for clarity. To understand the meaning of the graph, consider the angle of elevation. If you are at the same height as the antenna you receive the maximum signal. Hence, at 0 degrees there is 5 dB of gain. If you are elevated to a height 40 degrees above the horizontal (320 degrees on the graph) then the signal has been reduced by 7 dB (half-way between the 5 and 10 dB marking across the center of the graph.) When you are directly above the antenna, the signal is reduced by 27 dB. Note that the angles do not imply distance, and the shape of the pattern does not imply some imaginary three-dimensional shape in space. The signal doesnвЂ™t form a three-dimensional volume with the shape of the pattern graph. The graph is a tool to determine the degree of attenuation at a particular angle relative to the antenna. It is true, from a purely visual perspective, that the shape of the pattern gives a good indication of where the signal will be strong or weak, as if it actually were a three-dimensional volume (e.g., expanded in some directions, shrunk inwards in other directions.) Do not be confused, though, into thinking that the graph is intended to show you a three-dimensional shape. RapidNet Pre-terminated network cabling Tim Data Center Manager I need: FAST AND EASY INSTALLATIONS CATEGORY 6 AND FIBER OPTIONS GUARANTEED RELIABILITY ON TIME PROJECT COMPLETION (i.e. Can you п¬Ѓnish the cabling in one day?) RapidNet is the ideal high performance solution to keep your data center project on-time and operating with optimal results. Proven to reduce installation time more than 85% over traditional methods, the patented RapidNet cassette simply clicks into a modular 19вЂќ patch panel. RapidNet installations are fully warranted for guaranteed performance and each link is factory terminated and tested in a quality controlled environment. With a little help from RapidNet, upgrading or installing your network has never been easier. p h o n e: [8 0 0] 8 2 2 4 3 5 2 e m a i l: i n f o@h t a m e r i c a s . c o m w w w. h e l l e r m a n n .t y t o n . c o m / b i c s i Dan Contractor Done. (With a little help from RapidNet.) Antenna Beamwidth The term beamwidth is confusing because it assumes you know how the вЂњwidthвЂќ part is being measured. Beamwidth is an angle, measured on an elevation pattern graph that intersects the pattern at the points where the signal power has been reduced by 3 dB. Because a 3 dB reduction is equal to a 50 percent reduction youвЂ™ll often hear beamwidth referred to as half-power beamwidth (HPBW). If you examine an elevation pattern graph you can determine the points where the pattern has been reduced by 3 dB. These are shown as green dots on the 40-degree Half-Power Beamwidth diagram in Figure 5. The angle formed between these points (40 degrees in the diagram) is the HPBW angle. It is very important to realize that the HPBW angle is not an absolute barrier, beyond which no signal is transmitted. As can be seen by studying the example, even at double the HPBW angle, the signal has dropped -7 dB from the maximum; it has not disappeared completely. Here is why this is important. Consider a dipole on a mast, 30 feet in the air. At first thought it might be a concern that the pattern graph shows what looks like a dead spot directly below the antenna. It is not dead; it is just down by greater than roughly 50 dB. Over 30 feet, the signal reduction through the air (free space path loss) is roughly 60 dB. The receiver on the ground, directly Figure 5. 40 Degree Half-Power Beamwidth underneath the antenna, suffers 50 dB loss from the antennaвЂ™s pattern and the 60 dB loss from the signal propagation. If the transmitter were operating at 100 mW (20 dBm) then: 20 dBm вЂ“ 50 dB вЂ“ 60 dB = -90 dBm. That is still enough for a 1 Mbps or 6 Mbps 802.11 connectionвЂ”enough, but not optimal. As the user walks away from the point directly underneath the antenna, there is more path loss but the degree of loss from the pattern of the antenna diminishes even more quickly so the weaker coverage area remains very small. Conclusion: Applying ManufacturerвЂ™s Specifications To design an antenna system you first must know the TPO for your transmitter and the required RSSI for your receiver. You then calculate the loss across the path between the two. Now you select antennas with sufficient gain in the appropriate direction to allow the transmitter to reach the receiver at or above the minimum required signal strength level. The relationship between these metrics is: TPO + TransmitterGain вЂ“ Path Loss + ReceiverGain => RequiredRSSI This is called the Path Loss Equation, and itвЂ™s the basis for any Wi-Fi or other wireless network system. . Joe Bardwell Joe Bardwell is chief scientist with Connect802 Corporation, a systems integrator and wireless network design consulting firm based in California. Joe can be reached at +1 925.552.0802 or at joe@Connect802.com. 32 Advancing Information Transport Systems www.bicsi.org Feature Increasing Power Margin with High-Performance Optical Fiber Specify lower loss cable and optical fiber rated for longer distances than the intended use. BY ANDREW OLIVIERO Channel Insertion Loss Reduction Certain network configuration and connection assumptions were made by IEEE to establish the power budgets for 10GBASE-SR at 300 m (see Figure 1, column A). According to the link model, 77 percent of the total link power penalty of 7.3 dB is caused by CIL (accounting for 36 percent, at 2.6dB) and by ISI (41 percent, 3.0 dB). Therefore, improving CIL or ISI power penalties, or both, is the easiest way to create power margin. One strategy for reducing CIL directly is to improve cable attenuation and connection loss. This strategy involves the use of: вЂў Small form factor (SFF) connectors (e.g., LC connectors). вЂў Optical fiber with improved core centering tolerances to improve core to core alignment: - Low core/clad concentricity error (< 1.5 mm). - Tight clad diameter tolerance (125 +/- 1 mm). 34 Advancing Information Transport Systems www.bicsi.org - Tight core diameter tolerance (+/- 2.5 mm). вЂў Low 850 nm optical fiber attenuation (< 2.3 dB/km). вЂў A bend-insensitive coating. вЂў Low 850 nm cable attenuation (< 3.0 dB/km) Reduce the Inter-Symbol Interference Penalty In addition to creating power margin by directly improving CIL, margin can also be created by lowering ISI power penalties. In fact, the most significant way to Figure 1 10 Gb/s 850nm Serial Power Penalties 8 7 Power Penalty (dB) In planning for a LAN, data center, or storage area network, network designers must ensure that the optical fiber products they specify can provide the performance and reliability they need. Specifically, they may want to provide power headroom to increase their channel insertion loss budgets for such things as additional connections or higher loss connectors, and to improve overall reliability. This is especially critical in 850 nm 10 gigabit Ethernet applications, since channel insertion loss budgets for these systems are lower than previous applications. There are two keys to achieving greater power headroom, also known as power margin: 1. Reducing Channel Insertion Loss (CIL). CIL is the endto-end loss resulting from all connections and splices in the link, plus the attenuation of the cable itself. 2. Reducing Inter-Symbol Interference (ISI) by using a higher-bandwidth optical fiber. ISI occurs when bits of data run together due to high differential mode delay (DMD), causing low bandwidth in the optical fiber. 6 Other Other ISI CH IL ISI 3 2 Safety Margin ISI 5 4 Other CH IL CH IL 1 0 A) IEEE Standard based on OM3-300 Fiber B) Maximize Channel Insertion Loss using OM3-550 Fiber C) Maximize Safety Margin using OM3-550 Fiber Figure 2 If ISI is reduced . . . ISI Channel Insertion Loss can increase . . . Loss bandwidth for lasers that launch power in the optical increase the power marginвЂ”and create a higher CIL fiberвЂ™s center. This, along with higher resolution DMD budgetвЂ”is to reduce the actual ISI penalty of the link. ISI measurements, help ensure that the optical fiber cable can is lowered by lowering DMD and increasing the bandwithstand deviations in laser characteristics over time. width of an optical fiber for a given link distance. The вЂњpulse spreadingвЂќ that causes ISI is a result of DMD. Multimode optical fiber is so named because it has High Bandwidth, High Performance hundreds of light pathways, or modes, in which light can Interestingly, one can trade the power headroom travel along the core of the optical fiber. If the speed of attained by improving the ISI penalty to increasing the the light in each mode is equal, then all modes arrive at channel insertion loss, shown in Figure 2. the transceiver at the same time; in other words, the optical fiber will have zero DMD. But imperfections in optical fiber manufacturing and design can result in large differences in modal speed, causing DMD to increase. If the laser transmits a pulse into an optical fiber with high DMD, different parts of the laser pulse will travel along the optical fiber at different speeds. As a result, some parts of the pulse may spread into the adjacent bit slots, causing the system to fail. Controlling and minimizing DMD minimizes the ISIвЂ”and therefore maximizes the bandwidthвЂ”of a multimode optical fiber system. Using an optical fiber with low DMD can dramatically improve system performance while preserving the low cost benefits of multimode optical fiberNew Megger SCT2000 based systems. Thanks to advancements in DMD Structured Cable Tester testing (see next page), it is now posThe SCT2000 is the first tester to truly uncomplicate the certification and evaluation of copper and fiber cabling sible to produce optical fiber with installations. It is simply the must intuitive and easy-toaccurate, defect-free refractive index operate LAN certification tester on the market today! That alone makes it a tester to try. Now, add all of these profiles. The refractive index has to other impressive features: be well designed and controlled to в– 1 to 1,000 MHz frequency range. Certifies twisted pair to all ensure that all modes exhibit miniapproved ISO and TIA standard, including ISO Class F. в– Powerful diagnostics pinpoint the distance to link disturbances mal DMD and all arrive at the other on each measured pair. end of the optical fiber at the same в– Unique вЂњconnector-lessвЂќ recessed copper and fiber optic adapters eliminate virtually all potential adapter or tester time. No matter which modes in the damageвЂ¦keeping your SCT on the job. в– Unparalleled result storage capability. Internal memory stores optical fiber are actually guiding the over 5,000 certification test results, or 100 graphic results. light, those modes will have minimal в– Powerful certification management software organizes, edits, views, prints, saves or archives test results by job site, DMD and provide high bandwidth. customer, campus building and more. Designers should ensure that the в– Large color VGA LCD display provides a rich graphical user interface, speeding users through twisted pair and fiber optic optical fiber contained in the cable cabling certification and diagnosis. they purchase has been DMD-conв– вЂњTalkвЂќ feature allows two-way voice communication between the main and remote units. trolled to the very center of the optiReally? How easy is it? cal fiber. Selecting a multimode optiRequest a live demonstration at your location today by calling 1-800-723-2861 ext. 8518, email us at email@example.com or cal fiber with DMD specified in the go online to www.megger.com/sct for complete product specifications. zero to five Вµm range can double the ItвЂ™s already known as the easiest ever! WWW.MEGGER.COM BICSINEWS January/February 2007 35 What to Look for in Differential Mode Delay Testing DMD testing provides such a clear picture of how individual mode groups carry light down the optical fiber, and which mode groups are causing DMD, that the standards require optical fiber to be DMD-tested to ensure adequate bandwidth for the rated distances for 10 Gb/s applications. DMD testing involves transmitting short-duration, high-powered laser pulses in small steps across the entire core of the optical fiber. Each pulse excites only a few modes at each step, and the individual pulse shapes and arrival times are captured at the other end of the optical fiber. The DMD of the optical fiber is the difference between the earliest and latest arrival times of all pulses at all steps. From this information, adjustments can be made to the optical fiber manufacturing process to produce low DMD (high bandwidth) optical fiber. With a highly advanced process By specifying a higher-bandwidth optical fiber, a designer can trade off bandwidth headroom to increase CIL budgets. For example, many designers specify use of 850 nm laser-optimized 10 Gb/s multimode optical fibers (known as OM3 optical fibers) in data centers. If this optical fiber is used at distances shorter than its maximum rating, the ISI penalty is reduced and the вЂњliberatedвЂќ power (e.g., bandwidth headroom) can be devoted to increasing the CIL budget. The result is that designers of data centers or LANs can use вЂњplug and playвЂќ connectivity solutions, and can support the high loss of some of these systems while supporting bandwidth and reach requirements. Consider an 850 nm laser optimized multimode, 10 Gb/s cable solution rated to 550 meters under typical conditions. If this optical fiber is used to shorter distances (e.g., 300 meters), 1.9 dB of power headroom is created from the extra bandwidth. This can be added to the 2.6 dB of budgeted CIL to allow a total of 4.5 dB of CIL, shown in Figure 1, column B. This can now be devoted to the higher-loss connections of some MTP/MPO cassettes that are used with a plug and play design in a data center or LAN. This level of performance can also be achieved by using a 300 m rated 850 nm laser optimized multimode optical fiber product to 150 meters. Conclusion Because network downtime can be very expensive, reliability is a key requirement for high performance networks. These two strategies provide more power margins to enable greater flexibility in network design and, ultimately, greater reliability (Figure 1, column C). First, it is wise to specify lower loss cables and connectors that provide more power margins to enable higher levels of performance. Second, to provide more power margins to enable higher levels of performance and reliability, it is wise to specify an optical fiber that is rated for a longer distance than what it will be used for. When it comes to demanding 10 gigabit Ethernet optical fiber applications, do not assume that all products that meet a particular standard are equal. In fact, it is possible to find higher performing products that exceed the standards. The most cost-effective solution is OM3 optical fibers that have been designed and manufactured specifically for laser transmission. These are available in various performance grades, all featuring a DMD-controlled core that helps ensure 10 Gb/s support with low-cost 850 nm serial applications up to their rated distances. These optical fibers also support 1 Gb/s operation, and their 50 micron core size couples sufficient power from LED sources to support legacy applications such as Ethernet, Token Ring, fiber distributed data interface (FDDI), and Fast Ethernet for virtually all in-building networks and most campus networks. . for making optical fiber, DMD testing serves as a powerful process control tool to main- Andrew Oliviero tain a precise refractive index profile, even to the center Andrew Oliviero is the senior product manager for optical fiber products at OFS and is located in its headquarters in Norcross, Georgia. For more information, call 888.342.3743 (USA) or +1 770.798.5555 or email firstname.lastname@example.org. region of its optical fiber. 36 Advancing Information Transport Systems www.bicsi.org Testing Multimode Optical Fiber: Importance of Controlling Launch Conditions Achieving consistent and reproducible loss measurements. BY MICHEL LEBLANC AND MARIO SIMARD For many years now, installation of multimode optical fiber networks has been very common for traditional Ethernet business applications as well as for military, aerospace and industrial control systems. Multimode optical fiber deployment is an ongoing trend that will likely continue to grow as many installations bring optical fiber as far as the desk. The relatively low cost of system components, as well as easy installation and maintenance, are the driving forces behind the popularity of these networks. When testing multimode networks, it is important to take into account certain particularities of multimode optical fiber by paying attention to critical test parameters and adapting testing techniques when appropriate; namely, controlling launch conditions to allow for better testing of the multimode optical fiberвЂ™s loss. This article discusses the inherent properties of multimode optical fiber and how controlling launch conditions will yield more reliable test results. Figure 1. Loosely coupled modes (high-order) are often attenuated at bends, connections and splices. 38 Advancing Information Transport Systems Launch Conditions and the Propagation of Light To fully understand the importance of launch conditions, it is worthwhile to first review the concept itself. Launch conditions refer to the distribution of light that is injected into an optical fiber, impacting transport capability (bandwidth) as well as loss of an optical fiber link. When the distribution of light launched into the optical fiber fills its core completely, the launch conditions and the optical fiber are said to be overfilled. When a fraction of the optical fiber core is filled with light, it is considered to be underfilled. Historically, the optimum level recommended by standards is 70 percent, but this percentage no longer has any real technical correlation to modern-day multimode optical fiber systems. In multimode optical fiber, there are many possible optical paths for light to travel. These paths are referred to as modes. All modes are not equal because they have different propagating characteristics and different sensitivities to external factors, such as bends and splices. Figure 2. Typical launch conditions from commonly used light sources. www.bicsi.org Launching light near the central axis of the optical fiber excites the lower-order modes, often called tightly coupled modes. In the highest-order modes, also called loosely coupled modes, a significant part of the power is located close to or even in the cladding, as shown in Figure 1. For these very-high-order modes, losses are usually high, even for a bend radius of a few centimeters. For graded-index optical fiber with a 50 or 62.5 Вµm core, a few turns around a mandrel with a radius of 1 to 1.5 cm, called a mode filter, filters out these higher-loss modes. When there is an optical fiber-to-fiber connection, splice or other interface, it is these higher-order modes that will be attenuated the most. Once in the cladding, light is coupled out through mode stripping, thus creating the loss. Light coupled into any specific mode will transfer to another mode only through what is called mode scrambling, which can be generated by microbends, splices, connectors and other factors. For additional information on mode scrambling, please refer to TIA/EIA-455-54B. When light from an optical sourceвЂ”surface or edgeemitting LED, laser, vertical cavity surface emitting laser (VCSEL), light from another optical fiberвЂ”is coupled into a multimode optical fiber, the lightвЂ™s launch conditions determine which modes will be excited or filled and to what extent. Refer to Figure 2. The type of light source used and the way it is coupled into the optical fiber will have a huge impact on the launch conditions. Generally speaking, surface-emitting LED sources have a wide angle and a relatively large emission surface. This means that the high-order modes will generally be excited or filled. Laser sources have a narrower emission surface; therefore, higher-order modes in the optical fiber would not be significantly filled. The laser light will most likely be coupled into a small group of modes, usually close to the center of the optical fiber. Unless additional launch conditions are used, testing insertion loss with a laser light source could yield misleading results. In other words, when an optical fiber is overfilled, it means that a large portion of the power is launched into the high-order modes. If loss is measured under this condition, the result will likely be conservative (higher measured loss) compared to that of a test performed with underfilled launch conditions. On the other hand, if loss is tested with a restricted or significantly underfilled launch, the test results will be overly optimistic (very low loss) and faults may not be identified. For example, when a connector ferrule is misaligned and a test is performed with one set of launch conditions, the unit may measure low insertion loss and indi- cate that the connector has passed the test, while with different launch conditions, the unit may measure unacceptable power loss. The loss measurement of an optical fiber plant that includes connectors is therefore highly dependent on the launch condition of the source that is used to carry out the test. Best practices recommend the use of an overfilled source followed by a five-turn mandrel-wrap mode filter (see TIA/EIA-455-34A). In general, a surface-emitting LED will provide overfilled (or close to overfilled) launch conditions, while edge-emitting LEDs and VCSELs are more likely to produce slightly restricted launch conditions. Lasers with multimode pigtails usually produce restricted launch conditions. Testing multimode loss with sources that have unknown launch conditions will yield very unreliable and unrepeatable results that can very often be too optimistic. 2007 BICSI Canada Conference Experience firsthand the learning and networking potential a BICSI conference holds in a bustling metropolis full of natural beauty and unique cultures. March 4-7 Vancouver, British Columbia, Canada www.bicsi.org BICSINEWS January/February 2007 39 Coupled Power Ratio Fiber Size An easy way to characterize the launch condition of a source is to measure the coupled power ratio (CPR). CPR is the ratio of the total power out of a multimode optical fiber to the power measured when a singlemode optical fiber is coupled into the multimode optical fiber. The CPR is often used to evaluate the launch conditions of transmitters and light sources into multimode optical fibers and is used in TIA/EIA-526-14-A for establishing attenuation measurement criteria for installed optical fiber plants. A higher CPR means that there is high loss when coupled into the singlemode optical fiber and indicates a more fully filled launch, whereas a low CPR indicates restricted launch conditions corresponding to an underfilled optical fiber. When measuring CPR, it is important to use singlemode optical fibers at 850 and 1300 nm because these optical fibers have a mode-field diameter of approximately 9 Вµm at 1300 nm and 5 Вµm at 850 nm. As shown in Tables 1 and 2, the TIA/EIA-526-14-A standard has identified five categories for 50 Вµm and 62.5 Вµm optical fiber at 850 nm and 1300 nm. For detailed information on the five categories and on CPR measurement procedures, refer to TIA/EIA-526-14-A. The CPR will affect loss measurements differently, depending on the type of light source and filter used. With a category 5 source, which is very underfilled, the loss results will be highly optimisticвЂ”the link will seem to have very low loss. With a category 1 source, which is overfilled, the results will be conservative. Measuring Under Controlled Launch Conditions To ensure optimum multimode loss measurements, some multimode test and measurement devices control launch conditions to provide consistent and reproducible loss measurements. For devices used to test both 50 Ојm and 62.5 Ојm core optical fiber, when testing 50 Ојm optical fiber, use of a mode filter, consisting of five-turns mandrel with a diameter of 25 mm at the output of the device, is recommended for accuracy. What does that mean in day-to-day tests? As an example, suppose a test is performed on a 50 Ојm optical fiber, with two connections, using two different types of test equipment. The reference source is a LED at 850 nm with optimum launch conditions (CPR category 1 for 50 Ојm) with an external mode filter applied to the launch optical fiber output. After the LED source has been referenced on a power meter, the loss measured on the optical fiber under test is 0.5 dB (optical fiber loss and connectors included). The same optical fiber is now tested with an 40 Advancing Information Transport Systems www.bicsi.org 50/125 62.5/125 Categories Categories 1 to 3 4 and 5 (CPR) (CPR) 11-24 14-29 0-10.9 0-13.9 Table 1. Light source CPR values (in dB) for 850 nm. Fiber Size 50/125 62.5/125 Categories Categories 1 to 3 4 and 5 (CPR) (CPR) 8-20 12-25 0-7.9 0-11.9 Table 2. Light source CPR values (in dB) for 1300 nm. underfilled 850 nm FP laser source referenced on the same power meter, now showing a loss of 0.2 dB. If the pass/fail threshold for this cable was set at 0.4 dB, the testing device would pass for the FP laser source but fail for the LED. In this example, measurements using two different instruments with different launch conditions produce random loss readingsвЂ”sometimes right on target and sometimes too optimistic. This is not surprising, especially when using laser sources such as Fabry-Perot or VCSEL; when lasers are used in sources, they usually produce underfilled conditions. Conclusion Launch conditions for test equipment varies, even from a single test equipment manufacturer. Testing without knowing the launch conditions can result in getting a passing result when in reality the circuit should be failed, as when there is a misaligned connector. This could also lead a technician to misinterpret instrument results, try another test from another instrument, and extend the time and cost of the project. As a general rule, it is always best to specify launch conditions. Military, aerospace and industrial applications will most likely require category 1 or category 2 testing, as there is no room for failure. Category 1 to category 3 testing may be fine for less critical or less cost-sensitive applications. In all cases, category 4 to 5 testing should be avoided to obtain reliable measurements. . Michel Lebanc Mario Simard Michel Leblanc is senior technical advisor and Mario Simard is product manager for EXFO, a manufacturer of test and measurement equipment headquartered in Quebec, Canada. For more information, contact Mario at email@example.com or at +1 418.683.0913, ext. 3129. BICSI UPDATE New Design for Web Site Revised Design Course Keeps Pace with ITS Industry If you are an aspiring RCDDВ® or already have your designation, the revised training courseвЂ”DD102: Designing Telecommunications Distribution SystemsвЂ”is for you. Since this training course was last revised in 2003, a lot has changed in the design of distribution systems. This is why the new DD102 offers important training for any information transport systems (ITS) professional. In the new DD102, over 40 percent of the content has changed; over 90 percent of the images have been revised, too. The intensive, six-day course still focuses on the fundamentals of designing a structured cabling system. However, you will find some new features that improve your learning experience, including the following: вЂў Twelve structured exercises reflecting real world conditions that build upon each other during the week вЂў Updated final exercise that takes you through responding to quote request and bidding the project вЂў New student guide that closely follows the class, contains review questions, and contains chapter and page references to the Telecommunications Distribution Methods Manual (TDMM). DD102 topics include: вЂў Codes, standards and regulations вЂў Principles of transmission вЂў Electromagnetic compatibility вЂў Telecommunications spaces вЂў Work areas вЂў Horizontal distribution вЂў Backbone distribution вЂў Grounding, bonding and electrical protection вЂў Firestopping вЂў Telecommunications administration вЂў Design, construction and project management вЂў Networking fundamentals, including VoIP and wireless вЂў CO-OSP and campus cabling For more information or to register for DD102, call +1 813.979.1991 or 800.242.7405 (USA and Canada toll-free) or visit www.bicsi.org. As a first step in the redesign of the BICSI Web site, a new graphic template has been introduced that better reflects BICSIвЂ™s colors and logo. The next steps in the coming months include improving navigation to make it easier to find information as well as new content so that members can obtain up-to-date, complete information on products and services. See for yourself by visiting www.bicsi.org. BICSI Conference Schedule 2007 Canada Conference March 4-7, Vancouver, British Columbia, Canada 2007 Spring Conference April 15-18, Dallas, Texas 2007 South Pacific Conference March 26-28, Sydney, Australia 2007 European Conference June 18-20, Dublin, Ireland 2007 Middle East & Africa Conference April 1-3, Dubai, UAE 2007 Fall Conference September 10-13, Las Vegas, Nevada BICSINEWS January/February 2007 41 BICSI UPDATE Manual Reflects Broader Outside Plant Marketplace You will notice a slight difference in the title for BICSIвЂ™s new 4th edition outside plant (OSP) manual, to be published during the first quarter of 2007: Outside Plant Design Reference Manual (OSPDRM). This new edition, formerly known as the Customer-Owned Outside Plant (COOSP) Design Manual, now reflects the broad application of design and construction issues for OSP owned by customers or service providers. BICSIвЂ™s Technical Information and Methods (TI&M) Committee and Board of Directors agree that changing the name for this latest edition invites a broader readership. The fourth edition of the OSPDRM will be unique in many ways. As with other recent manuals, the OSPDRM will address global best practices, supported by relevant codes and standards at the end of each chapter. Content changes include an important chapter on legal considerations that discusses some of the issues and problems that are common on OSP projects; updated information on cost estimating; grounding, bonding and protection; cable types; and design considerations for overbuilds. To order your OSPDRM, call +1 813.979.1991 or 800.242.7405 (USA and Canada toll-free) or visit www.bicsi.org. 2007 Region Meetings U.S. Northeast Region Meeting March 1, 2007 FiberOptic.com Corporate Complex Allentown, Pennsylvania US Western/South-Central Region Meeting March 13, 2007 Venue TBD, Phoenix, Arizona U.S. Southeast Region Meeting March 22, 2007 OFS Factory, Atlanta, Georgia U.S. Northeast/North-Central Region Meeting May 16, 2007 Charleston Civic Center Charleston, West Virginia U.S. Southeast Region Meeting June 28, 2007 Venue TBD, Charlotte, North Carolina U.S. Northeast Region Meeting July 23, 2007 Venue TBD, Harrisburg, Pennsylvania U.S. Western Region Meeting July 24, 2007 Honolulu Community College, Honolulu, Hawaii U.S. Northeast Region Meeting October 18, 2007 CXtec Facility, Syracuse, New York U.S. Southeast Region Meeting October 18, 2007 Venue TBD, Jacksonville, Florida 42 Advancing Information Transport Systems www.bicsi.org BICSI Courses For more information about courses, please contact BICSI at +1 800.242.7405 (USA/Canada toll free) or +1 813.979.1991 or visit www.bicsi.org. February 2007 4вЂ“9 DD102 Designing Telecommunications Distribution Systems, 5вЂ“8 DD200 Telecommunications Distribution Design Review, 5вЂ“9 IN100 ITS Installer 1 Training, Indianapolis, IN 12вЂ“16 IN100 ITS Installer 1 Training, Tampa, FL 12вЂ“16 IN200 ITS Installer 2 Training, Tampa, FL 18вЂ“23 DD102 Designing Telecommunications Distribution Systems, Tampa, FL 19вЂ“20 DD100 Introduction to Voice/Data Cabling Systems, Phoenix, AZ 19вЂ“22 DD200 Telecommunications Distribution Design Review, Tampa, FL 19вЂ“23 IN200 ITS Installer 2 Training, Providence, RI Indianapolis, IN Indianapolis, IN 21вЂ“23 OSP101 Site Survey and Media Selection, Phoenix, AZ 2/26вЂ“3/2 TE300 ITS Technician Training, Providence, RI 2/26вЂ“3/3 DD102 Designing Telecommunications Distribution Systems, 27вЂ“28 DD100 Introduction to Voice/Data Cabling Systems, 27вЂ“28 WD100 Introduction to Wireless, Allentown, PA 2/27вЂ“3/2 DD200 Telecommunications Distribution Design Review, Vancouver, BC Vancouver, BC Allentown, PA March 2007 5вЂ“9 IN100 ITS Installer 1 Training, Tampa, FL 8вЂ“9 DA100 Introduction to Networks, Vancouver, BC 8вЂ“9 DD100 Introduction to Voice/Data Cabling Systems, Vancouver, BC 12вЂ“15 DD200 Telecommunications Distribution Design Review, Columbus, OH 12вЂ“16 IN200 ITS Installer 2 Training, Columbus, OH 12вЂ“16 IN200 ITS Installer 2 Training, Tampa, FL 18вЂ“19 DD100 Introduction to Voice/Data Cabling Systems, Tulsa, OK 19вЂ“23 IN100 ITS Installer 1 Training, Tulsa, OK 19вЂ“23 TE300 ITS Technician Training, Tampa, FL 19вЂ“23 WD110 Designing Wireless Networks, Tulsa, OK 20вЂ“23 DD200 Telecommunications Distribution Design Review, Tulsa, OK 25вЂ“30 DD102 Designing Telecommunications Distribution Systems, Tampa, FL 26вЂ“29 DD200 Telecommunications Distribution Design Review, Tampa, FL DD = Distribution Design DA = Data Distribution Design TE = Cabling Installation WD= Wireless Design OSP= Outside Plant Design BICSINEWS January/February 2007 43 BICSI Courses BICSI World Headquarters For more information about courses, please contact BICSI at +1 800.242.7405 (USA/Canada toll free) or +1 813.979.1991 or visit www.bicsi.org. 8610 Hidden River Parkway, Tampa, FL 33637-1000 USA +1 813.979.1991 or 800.242.7405 (USA & Canada toll-free); Fax: +1 813.971.4311; Web site: www.bicsi.org; E-mail: firstname.lastname@example.org April 2007 2вЂ“6 IN100 ITS Installer 1 Training, Tampa, FL 9вЂ“13 DA110 Designing Networks, Dallas, TX 9вЂ“13 OSP110 Cable Plant Design, Dallas, TX 9вЂ“14 DD102 Designing Telecommunications Distribution Systems, Dallas, TX 10вЂ“14 IN100 ITS Installer 1 Training, Dallas, TX 10вЂ“14 WD110 Designing Wireless Networks, Dallas, TX 11вЂ“14 DD200 Telecommunications Distribution Design Review, Dallas, TX 12вЂ“14 DA200 Network Design Specialty Review, Dallas, TX 12вЂ“14 WD200 Wireless Design Specialty Review, Dallas, TX 13вЂ“15 OF100 Optical Fiber Installation Theory and Technique, Dallas, TX 16вЂ“18 TT100 Testing, Certifying and Troubleshooting Copper and Fiber, Dallas, TX BICSI Executive Staff Executive Director David C. Cranmer, RCDD, email@example.com Professional Development and Credentialing Director Richard E. Dunfee, firstname.lastname@example.org Director of Administration and Chief Financial Officer Betty M. Eckebrecht, CPA, email@example.com Conferences and Meetings Director Georgette Palmer Smith, CMM, firstname.lastname@example.org Director of International Operations Jan Lewis, email@example.com 16вЂ“20 IN200 ITS Installer 2 Training, Dallas, TX 16вЂ“20 TE300 ITS Technician Training, Tampa, FL 19вЂ“20 DA100 Introduction to Networks, Dallas, TX BICSI News Staff 19вЂ“20 DD100 Introduction to Voice/Data Cabling Systems, Dallas, TX 19вЂ“20 OSP100 Introduction to Customer Owned Outside Plant, Dallas, TX Editor Michael McCahey, firstname.lastname@example.org 19вЂ“20 WD100 Introduction to Wireless, Dallas, TX 19вЂ“21 DD120 Grounding and Protection Fundamentals for 19вЂ“22 FO110 Fiber Optic Network Design, Dallas, TX 22вЂ“27 DD102 Designing Telecommunications Distribution Systems, Tampa, FL 23вЂ“26 DD200 Telecommunications Distribution Design Review, Tampa, FL 23вЂ“27 IN200 ITS Installer 2 Training, Tampa, FL 23вЂ“27 TE300 ITS Technician Training, Dallas, TX Telecommunications Systems, Dallas, TX DD = Distribution Design DA = Data Distribution Design TE = Cabling Installation Publication Coordinator/Designer Wendy Hummel, email@example.com Copy Editor Clarke Hammersley, firstname.lastname@example.org Copy Editor Joan Hersh, email@example.com BICSI International Staff European Office Supervisor: Laura La Porta +32 2 789 2333, firstname.lastname@example.org WD= Wireless Design OSP= Outside Plant Design Japan District Manager : Kazuo Kato +81 3 3595 1451; email@example.com Mexico Office Representative: Gilberto Ferreira Ruiz, RCDD +52 55 5638 1228; firstname.lastname@example.org South Pacific Office Manager: James Armytage + 61 3 9813 3355; email@example.com The BICSI News is published bimonthly for BICSI, Inc., and distributed to BICSI members and BICSI Registered ITS Installer 1, ITS Installer 2, ITS Technicians; and Residential Installers. Articles of a generic nature are accepted for publication; however, BICSI reserves the right to edit these for space or other considerations. Opinions expressed in articles in this newsletter are those of the writers and not necessarily of their companies or BICSI. В© Copyright BICSI, 2007. All rights reserved. BICSI and RCDD are registered trademarks of BICSI, Inc. Printed in the USA. 44 Advancing Information Transport Systems www.bicsi.org Standards Report TSB-155 Approved The development process was long and tedious but TSB-155 has finally been approved. And now we wait for ANSI/TIA/EIA-568B.2-10, but why do we need either? Donna Ballast, In May 2002, ANSI/TIA/EIARCDD 568B.2-1 Transmission Performance firstname.lastname@example.org Specifications for 4-pair 100 ohm Category 6 Cabling was published. This standard characterized category 6 cabling from 1 MHz to 250 MHz. When IEEE 802.3an group began their work, they asked for additional bandwidth characterization of the installed base. The groupвЂ™s original goal was 625 MHz over some length of category 5e and 100 meters of category 6. TIA agreed to do the work and a new demon was identifiedвЂ”alien crosstalk. In June 2006, the IEEE 802.3an 10-gigabit Ethernet (10GBase-T) standard was approved. This standard established physical coding and sublayer interface for 10GBase-T applications over balanced twisted-pair copper cabling systems. It also established signaling and interference requirements for semiconductor chips that will support 10Gb/s performance and specified four connector channel electrical requirements for augmented category 6/Class EA, class F, and category 6/class E cabling systems (over the frequency range from 1 MHz to 500 MHz). In December 2006, TSB-155 Guidelines for the Assessment of Category 6 Cabling in Support of 10-Gigabit Applications was approved for publication. These guidlines provide a means to determine if a category 6 permanent link or channel meets the requirements of ANSI/TIA/EIA568-B.2-1 from 250 MHz to 500 MHz and is sufficiently immune to alien crosstalk. Logically, any noise from outside the victim (or disturbed) cable would be alien crosstalk, but TIA defines alien crosstalk as вЂњunwanted signal coupling from a disturbing pair of a four pair channel, permanent link, or component to a disturbed pair of another four pair channel, permanent link, or component.вЂќ In TSB 155, alien crosstalk is specifically вЂњcrosstalk coupling between four pair category 6 cabling in close proximityвЂќ to the victim cable. Why? Anything else would be much more difficult, if not impossible, to field test. Depending on the alien crosstalk environment, 10GBase-T should operate over channel lengths between 37 and 55 meters of category 6 cabling. At less than 37 meters, alien crosstalk should not be a problem but that can only be verified by testing. According to TSB 155, field test equipment used for assessment of category 6 cabling to TSB-155 guidelines should meet the accuracy requirements for level IIIe field testers in ANSI/TIA/EIA-568-B.2-10 Annex I. So what if you test the category 6 channel and it is longer or doesnвЂ™t measure up? Mitigation procedures are also provided. If the failure is anything other than alien crosstalk, there is the list of options in TSB 155 Annex B from BICSINEWS January/February 2007 45 Standards Report-continued which to choose, one by one, retesting after each until the channel passes: Option 1вЂ”Replace the work area, patch, and/or equipment cords with category 6A cords. Option 2вЂ”Reconfigure the cross-connect as an interconnect. Option 3вЂ”Replace the consolidation point connector with a category 6A consolidation point connector. Option 4вЂ”Replace the work area outlet connector with a category 6A work area outlet connector. Option 5вЂ”Replace the cross-connect or interconnect with a category 6A cross-connect or interconnect. Then there is Option 6, which is implied but not on the listвЂ”replace the horizontal cable with category 6A. If the failure reported is alien crosstalk, there is another list in TSB 155 Annex C to follow, again retesting after each until the channel passes: 1. When selective deployments of 10GBASE-T applications are possible, utilize non-adjacent patch panel positions (patch panel adjacency should also be checked at the rear of the patch panel), separate the equipment cords and unbundle the horizontal cables. 2. When deploying 10GBASE-T applications in adjacent patch panel positions, in the telecommunications room, testing is recommended; the number of disturbed channels to be tested should be determined using statistical sampling techniques based upon the intended confidence level. a. Identify measured patch panel positions to be included in the power sum. b. Select and test those channels with connectors adjacent to, or cable segments in the same bundle as, the disturbed channel. For these channels, test the alien crosstalk to be included in the power sum calculation following the procedures in clause A.9. mitigate the alien crosstalk coupling such as category 6 ScTP and category 6A. c. Reconfigure the cross-connect as an interconnect. d. Replace connectors with category 6A. e. Replace the horizontal cable with category 6A. A Few Noteworthy Points TSB 155 clause A.9 does not exist. ANSI/TIA/EIA-568B.2-10 is currently still in committee and, according to industry sources, publication is not likely until late 2007 or early 2008. No TIA standard exists that specifies transmission requirements for category 6A cabling. Nor does вЂњAnnex I,вЂќ which specifies accuracy requirements for level IIIe field testers. Until ANSI/TIA/EIA-568-B.2-10 is actually published, those requirements currently in the drafts are not fixed. What may seem to be small changes in wording can have a huge impact on your bottom line. For example, ANSI/TIA/EIA-568-B.2-10 Draft 5 allows for вЂњnormalizationвЂќ of power sum attenuation to alien crosstalk ratio far-end (PSAACRF). PSAACRF is a вЂњcomputation of the unwanted signal coupling between cabling or components in close proximity from multiple disturbing pairs at the near end into a disturbed pair at the far end, and relative to the received signal level in the disturbed pair at the far-end.вЂќ However, there are dissenters within the TIA TR42 committee who want to delete PSAACRF normalization. Small change? Big surprise? Remember, the sole purpose for developing category 6A cabling was to support 10GBase-T applications over 100-meter UTP channels. Remove PSAACRF normalization from the current specifications (ANSI/TIA/EIA-568B.2-10 Draft 5) and UTP cabling would NOT routinely pass category 6A field testing, even though the links and channels would support all 10GBase-T applications. However, shielded cabling systems would pass without PSAACRF normalization. Contractors Beware! 3. In the event that the alien crosstalk transmission parameters given in either 6.1 or 6.2 are not met in step 2, the alien crosstalk may be mitigated by the following procedure: a. Reduce the alien crosstalk coupling by separating the equipment cords and the patch cords and unbundling the horizontal cabling. b. An alternative to separating equipment cords is to utilize equipment cords sufficiently specified to 46 Advancing Information Transport Systems www.bicsi.org UTP copper cabling is not the only media choice that supports 10GBase-T. ScTP category 6, which meets the requirements of ANSI/TIA/EIA-568-B.2-1 from 250 MHz to 500 MHz and Class F cabling systems, also supports 10GBase-T applications. If you are bidding on design and installation projects for category 6A cabling, make certain that a fixed set of cabling requirements is part of your contract documents, and not just a reference to a document that is still evolving. . Jack be Nimble Jack be Quick Pick your category. Choose your colors. Decide on straight or angled. Click the cap for quick change. One jack does it all. Our jacks are specifically engineered to give you flexible options. TheyвЂ™re easy to install. And save you time. We help you make great connections.в„ў 1-800-544-1948 www.uniprisesolutions.com В©2006 CommScope, Inc. All Rights Reserved.All trademarks identified by В® or TM are registered trademarks or trademarks, respectively, of CommScope.