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WHITE PAPER TrueNet® Technical Reference Technical Reference Industry Standards The Benefits of Standards Entrance Facilities and Equipment Rooms 1/05 • xxxxxxx TrueNet® Technical Reference Telecommunications Rooms Backbone Cabling (Interbuilding) Intermediate Cross-Connects Horizontal Cabling Backbone Cabling (Interbuilding) Work Area Telecommunications Rooms Main Cross-Connect The TIA/EIA-568-B Series standard defines a typical, generic telecommunications cabling system Imagine trying to link railroads together that are based on different gauges, to build anything with a combination of metric and American parts, to type a letter on something other than a QWERTY keyboard, or to wire a building for voice, data and video if all the components had different requirements The key to simplifying all these tasks is standardization Bringing standards to the wiring and cabling segments of the building industry has enabled the industry to define a common infrastructure that allows many companies to provide common components Strict adherence to these standards benefits everyone ADC’s Position on Standards ADC is a strong proponent of standards-based design for structured cabling systems A strictly defined set of standards helps ensure uniform application of physical layer networking products and creates a usable infrastructure for communications networks However, ADC also believes that by nature, the standards evolve into a lowest-common denominator indicator of performance In order to accommodate various competing interests, a significant amount of “flexibility” gets built into the allowable tolerances The cumulative effect of these tolerances can result in structured cabling channels in which different components can have radically different electrical performance characteristics Consequently, when various standards-compliant components from randomly selected vendors are used, the net result could be conformance to the standards, but not efficient performance The research undertaken by ADC for the TrueNet® structured cabling system revealed that only a well-matched structured cabling channel that conforms to a tightly defined subset of the performance standards is capable of flawless data transmission ADC, as a full system supplier, is able to deliver a complete system of well-matched components so there is no guesswork Choosing standards-compliant components randomly from unrelated vendors will yield a standards-compliant channel, but may not result in optimum network performance Therefore, use the standards as a design guide, then make sure that you purchase standards-compliant matched components w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Entrance Facilities 1/05 ã xxxxxxx TrueNetđ Technical Reference The entrance facility provides a connection point between the outside plant facilities—whether it is public network services, private network customer premises or a combination of both—and the interior premises cabling Products used in this area include cables, connecting hardware, special protection devices and other connecting hardware The demarcation point separating the service provider’s cabling and the customer’s cabling may be part of the entrance facilities Because the location of the demarcation point is determined by state and federal regulations, the local regulated carrier (telephone service provider) or competitive access provider should be contacted for detailed information The primary standards for this area are outlined in TIA/EIA-569-A, Commercial Building Standard for Telecommunications Pathways and Spaces, and J-STD-607-A, Commercial Building Grounding/ Bonding Requirements ADC manufactures special overvoltage blocks, protection devices and building entrance terminals for both fiber and copper cabling for use in this area Equipment Rooms The TIA/EIA-568-B Series standard makes a distinction between equipment rooms and telecommunications rooms because of the nature of complexity of the equipment they contain However, an equipment room may alternately provide any or all of the functions of a telecommunications room Equipment rooms provide a controlled environment to house telecommunications equipment This equipment may include connecting hardware, splice closures, grounding and bonding facilities and protection devices, where applicable Switches, routers and other active equipment may reside in the same rack or cabinet space as the passive cabling infrastructure In the premises cabling backbone hierarchy, an equipment room may contain either the main cross-connect or the intermediate cross-connect The equipment room may also contain network trunk terminations and auxiliary terminations that are under the control of the premises cabling administrator The primary standards for this area are outlined in TIA/EIA-569-A, Commercial Building Standard for Telecommunications Pathways and Spaces ADC manufactures a wide variety of fiber and copper patch panels, termination blocks and cable management solutions that are well suited for this area Telecommunications Rooms Telecommunications rooms may provide various functions for the cabling system and because of this they are treated as a distinct subset in the cabling system hierarchy The primary function of a telecommunications room is to provide a termination point for horizontal cable distribution, that supports all voice, data, video and other applications requiring structured cabling The telecommunications room also serves as a termination point for backbone cable The cross-connection of these two parts of the premises cabling is an important function of the telecommunications room Cross-connections may be accomplished using jumper wires or patch cords, and ADC products handle both methods equally well Telecommunications rooms may also house cross-connects for different portions of the backbone cabling system These cross-connects are sometimes used to tie different rooms together in a ring, bus or tree configuration w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Telecommunications rooms also provide a controlled environment for specific areas of a building These rooms may house telecommunications equipment, connecting hardware and splice closures as well as devices such as routers and hubs In some instances, the demarcation point and protection devices may be located in a telecommunications room TrueNet® Technical Reference The TIA/EIA-568-B Series standard details cable routing and installation practices for telecommunications rooms to prevent cable stress and to properly organize and manage cables Additional standards for this area are outlined in TIA/EIA-569-A, Commercial Building Standard for Telecommunications Pathways and Spaces ADC manufactures a wide variety of blocks and patch panels capable of providing termination and cable management for a wide range of wire sizes and cable types found in telecommunications rooms For More Information Although this catalog presents a brief overview of information contained in the standard, persons involved with the installation and maintenance of structured cabling systems should obtain a copy of the complete standard and/or related standards TIA/EIA-568-B Series Horizontal Channel/Link Model Patch Cord Work Area Work Area Cable Telcom Outlet Station Field Equipment Field Data Hub FUSE ON Transition Point (Optional) 3M (Max) Station Cable OFF Equipment Cable 90M (Max) 7M A B ISO/IEC 11801 Horizontal Channel/Link Model Patch Cord Work Area Work Area Cable • xxxxxxx A + B < 10 M 1/05 Telcom Outlet Station Field Equipment Field Data Hub FUSE ON Transition Point (Optional) Station Cable 90M (Max) OFF Equipment Cable 5M (Max) A B E A + B + E < 10 M w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Technical standards that address various aspects of commercial cabling include: • TIA/EIA-568-B Series, Commercial Building Telecommunications Cabling Standard • TIA/EIA-569-A, Commercial Building Standard for Telecommunications Pathways and Spaces • TIA/EIA-606, Administration Standard for the Telecommunications Infrastructure of Commercial Buildings • J-STD-607A, Commercial Building Grounding/Bonding Requirements For information on obtaining copies of any of these standards, please contact: Global Engineering Documents 800.854.7179 or 303.397.7956 www.global.ihs.com ISO 11801 (International Standard) www.iso.ch NEC (National Electrical Code), written and distributed by the National Fire Protection Association (NFPA) www.NFPA.org A discussion of standards affecting the design and layout of a standards-based data center, as well as ADC’s recommendations for assuring that your data center supports the demands of, and grows with, your network, follows on page 28 1/05 • xxxxxxx TrueNetđ Technical Reference ã TIA/EIA-570-A, Residential Telecommunications Cabling Standard w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Interconnection vs Cross-Connection 1/05 • xxxxxxx TrueNet® Technical Reference Interconnection Cross-Connection The TIA/EIA-568-B Series standard addresses two basic wiring schemes for the telecommunications room: interconnection and cross-connection Both the backbone and the horizontal cabling are terminated on connecting hardware that meets the requirements of the TIA/EIA-568-B Series standard However, the standard prohibits the use of these terminations for moves, adds and changes Any connection between the backbone and horizontal cabling must be accomplished through the use of a “horizontal cross-connect” between the common equipment and the connecting hardware to which the horizontal cabling is terminated This connection may be made using an interconnection or a cross-connection cabling scheme An interconnection is a cabling scheme that provides for a direct connection between two cables without the use of patch cords or jumper wires A cross-connection is a cabling scheme between cabling runs, subsystems and equipment using patch cords or jumper wires that attach to connecting hardware on each end Common equipment that utilizes cables that extend an individual port may be permanently terminated or interconnected to the connecting hardware for the horizontal cabling Direct interconnections such as this reduce the number of connections in a channel, but may also reduce the flexibility, especially as the volume of moves, adds and changes increases w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Backbone Cabling The TIA/EIA-568-B Series standard requires that backbone cabling use a hierarchical star topology Each horizontal cross-connect in a telecommunications room is cabled to an intermediate cross-connect and then to a main cross-connect (or directly to a main cross-connect), with no more than two hierarchical levels of cross-connect in the backbone cabling These cross-connects may be located in telecommunications rooms, equipment rooms or entrance facilities Recognized cables for use in backbone cabling include the following: 100Ohm UTP (unshielded twisted pair) cable (four or more pairs) 150Ohm STP-A (shielded twisted pair) cable 62.5/125µm, multimode optical fiber cable Backbone cabling uses a hierarchical star topology 50µm, multimode optical fiber cable Singlemode optical fiber cable 1/05 ã xxxxxxx TrueNetđ Technical Reference Backbone cabling provides interconnections between the telecommunications rooms, equipment rooms and entrance facilities Backbone cabling consists of cables, main and intermediate cross-connects, mechanical terminations and patch cords or jumper wires Backbone cabling can be within buildings (intrabuilding) or between buildings (interbuilding) Intermediate Cross-Connects Telecommunications Rooms Main Cross-Connect w w w a d c c o m • + - - - 8 • - 0 - 6 - Technical Reference Industry Standards Horizontal Cabling 1/05 ã xxxxxxx TrueNetđ Technical Reference Horizontal cabling extends from the work area telecommunications outlet to the horizontal cross-connect in the telecommunications room Horizontal cabling includes the cables, the telecommunications outlet in the work area, the mechanical termination and patch cords or jumper wires and cable management solutions located in the telecommunications room • • • • • • • • • Voice service Internet service Video and conferencing services Premises switches, routers and hubs Data communications to support fax, storage servers, network printers Local area networks (LANs) Life safety systems such as security, fire alarm and door entrance Automation systems such as lighting and HVAC control Other building signaling systems, such as CCTV, nurse call, paging, audio and others Intermediate Cross-Connects Telecommunications Rooms Main Cross-Connect Relocation of offices is a common occurrence in enterprises Horizontal cabling is often one of the more dynamic areas of the premises system However, after installation, horizontal cabling is often much less accessible than backbone cabling, and the time, effort and skills required to change or modify it can be extremely high Horizontal cabling should be designed with the intention of minimizing ongoing maintenance and relocation so that moves, adds and changes can be accomplished from the telecommunications and equipment rooms Additional consideration should be given to accommodating a wide range of applications in order to reduce the necessity of changes to the cabling as users’ needs evolve Care should be given to separate telecommunications cabling from electrical facilities that generate high levels of electromagnetic interference (EMI) Fluorescent lights, copy machines, heating/cooling devices, motors and transformers that support the building’s mechanical requirements all contribute to EMI TIA/EIA-569-A specifies separation of horizontal cabling pathways from common sources of EMI Horizontal cabling is required to use a star topology Each work area telecommunications outlet is to be connected to a horizontal cross-connect in the telecommunications room Each work area is to be served by a telecommunications room Maximum Distances The maximum distance of a copper horizontal cabling run is 90 meters (approximately 295 feet) from the mechanical termination at the horizontal cross-connect in the telecommunications room to the telecommunications outlet in the work area Cross-connect jumper wires and patch cords used in the cross-connect facilities should not exceed six meters in length (approximately 20 feet) w w w a d c c o m • + - - - 8 • - 0 - 6 - 9 Technical Reference Industry Standards Horizontal Cables 100Ohm UTP (unshielded twisted pair) cable (four or more pairs) 150Ohm STP-A (shielded twisted pair) cable 62.5/125µm, multimode optical fiber cable 50µm, multimode optical fiber cable Color Codes for Horizontal 100Ohm UTP Cable or for Patch Cords Pair = White-Blue/Blue Pair = White-Orange/Orange Pair = White-Green/Green Pair = White-Brown/Brown 1/05 ã xxxxxxx TrueNetđ Technical Reference Recognized cables for use in horizontal cabling include the following: w w w a d c c o m • + - - - 8 • - 0 - 6 - 10 Technical Reference Industry Standards Work Area TrueNet® Technical Reference The work area components of a premises cabling system are the most visible to office workers Work area components extend from the telecommunications outlet to the station equipment, such as traditional telephones, VolP devices, networked computers, fax machines and shared devices such as network printers Because work area cabling is generally nonpermanent and relatively easy to change, it is not addressed in the TIA/EIA-568-A standard However, the length of cords used in the work area are assumed to be no longer than three meters (approximately 9.8 feet) in establishing the maximum length for the horizontal cabling of 100 meters total, and the cords should meet or exceed the requirements for patch cords outlined in the standard Common patch cords used in the work area have identical connectors on both ends, but cords may vary widely in design depending on the application Often adapters are required to accommodate specific equipment Types of adapters include: • Special adapters to mate an equipment connector to the telecommunications outlet when they are different styles (e.g baluns) • A “Y” adapter to branch two services off of a single cable • Adapter which transpose pairs for compatibility • Adapters for equipment that requires termination resistors Intermediate Cross-Connects Telecommunications Room 1/05 • xxxxxxx Main Cross-Connect These and other types of adapters can have a detrimental effect on the transmission performance of the telecommunications cabling system It is important to consider the compatibility of these adapters to premises cabling equipment before connecting them to the network A successful, high-performance premises wiring system requires more than simply purchasing the proper standards-compliant cables and hardware Care must be taken to ensure that the components are installed properly according to industry-recognized practices Performance specifications called out in the TIA/EIA-568-B Series standard are based on the assumption that proper installation techniques and management practices have been followed If recommended cabling precautions and installation methods are not observed, specified transmission capabilities of cabling components may not be achieved Installation should be performed by trained, certified installers such as the authorized ADC Cabling System Certifiers who are authorized to provide an ADC product and performance warranty w w w a d c c o m • + - - - 8 • - 0 - 6 - 11 Technical Reference 10Gigabit Ethernet over UTP: CopperTen™ Cabling Solution This effect is even more dramatic when viewed from the side of a cable bundle The peaks of the oblique, elliptical filler (red arrows) are used as the contact points along the length of the run These provide the greatest distance between the actual pairs by vaulting the sides of the ellipse (yellow arrows) where the pairs are housed The reduction of alien crosstalk is now greatly improved over the standard Category cable and the new CopperTen cable The improvements are approximately 20dB better on CopperTen cable than standard Category cable To put this in perspective: for every 3dB of extra noise there’s a doubling effect resulting in standard Category cable being more than six times noisier than CopperTen cable CAT ALIEN CROSSTALK SAMPLE W/CLASS F LIMIT 1/05 • xxxxxxx TrueNet® Technical Reference The separation can be better understood through the actual cross section below The unique design keeps cable pairs of the same twist rate within different cables at a greater distance from one another than in the past Similar to the patented AirES® technology cable design, air is used between these pairs AUGMENTED CAT ALIEN NEXT SAMPLE W/CLASS F LIMIT FREQUENCY FREQUENCY For the purpose of comparison, the Category limit line was used to show the dramatic improvement in preventing alien crosstalk This ability to create a future-proofing cable in the CopperTen solution brings up a question as to the need for standard Category cable, a cable sold and purchased (for the most part) in an effort to support the next technology leap The industry now has taken the next leap Copper UTP has been given another lease on life to support the next future proofing step in a 10Gigabit transport protocol The cost of active hardware will remain in check and be cost effective for future advancements in data transfer rate speeds w w w a d c c o m • + - - - 8 • - 0 - 6 - 19 Technical Reference Choosing the Right Ethernet Patch Panels Category, 5e, 6, or Augmented Category 6? IDC punchdown, or modular? T568A or T568B? Shielded or unshielded? How I ensure the integrity of my network? Can the infrastructure grow and change without service disruptions? With all the choices you face as you design your network and select equipment, including available Ethernet patch panels, it’s easy to become confused and frustrated Ultimately your choice of Ethernet panels should fit the applications you plan to run ADC has written this short tutorial to guide you through these decisions, to make them as painless as possible and offer you the best solution for your network First, let’s ask a few key questions Your answers will help guide you in the decision process Next, we will briefly discuss each of the most popular options available so you can draw conclusions based on your network needs Discovery Questions • What applications are you or you plan to run in this facility? Take into account not only what you are doing today, but what you probably will be doing tomorrow i.e 10/100Base-T? 1000Base-T? 10G Base-T? • What type of LAN network are you designing? Data center? Data backbone? Workstation? • Is the project a new network installation or an addition to an existing network? • Is the installation being built to expand existing capacity with current data capabilities or is it for new, faster data applications? Answers to these questions will guide you to a particular cable type, a particular data patch panel, and the means to terminate the cable into the patch panel—whether the terminations into the patch panel involve “punchdown” cable terminations, pre-made telco-type multi-pair cable ends, or standard RJ45 cable ends The general guidelines for network transmission capabilities segment the data network; data center and data network backbone system applications require the highest level of transmission capabilities, while feeds to work areas generally require a bit less However, all network connectivity should be designed with only the highest network engineering standards available Category 5e, and A6 Cabling The Telecommunications Industry Association (TIA) standards group consists of a variety of industry experts including connectivity and cable manufacturers, distributors, installers, and end customers The TIA determines certain transmission characteristics that must be met to qualify a cable for certain network applications 1/05 • xxxxxxx TrueNet® Technical Reference Will I choose the right Ethernet patch panel for my application? Will this choice work with future applications? Am I getting the best overall value? Category 5e is currently the minimum TIA recommended category of wiring for new installations Electrical characteristics for NEXT, FEXT, ELFEXT, PSNEXT, PSELFEXT, delay skew, propagation delay, attenuation, and return loss are specified to 100MHz Category 5e was developed with the specific intent of supporting Gigabit Ethernet Because all TIA standards require backwards compatibility, Category 5e will also support all lower-rated categories and protocols such as 10/100 Base-T Category is gaining popularity for new installations Electrical characteristics for NEXT, FEXT, ELFEXT, PSNEXT, PSELFEXT, delay skew, propagation delay, attenuation, and return loss are specified to 250MHz Improvements in all electrical parameters are part of the higher TIA Category standard Category 6, while providing a “bigger pipe” for improved throughput, also has a maximum 100 meters of support for Gigabit Ethernet transmission w w w a d c c o m • + - - - 8 • - 0 - 6 - 20 Technical Reference Choosing the Right Ethernet Patch Panels Augmented Category is the cutting edge of UTP cabling It is similar to Cat 6, but is characterized to 500MHz and is also capable of running 10Gigabit Ethernet protocols of the future Testing parameters are similar to that of Cat 5e and Cat 6, with the added benefit of compliance to Alien (Bundled) Crosstalk requirements 1/05 ã xxxxxxx TrueNetđ Technical Reference Definitions of cabling test parameters can be found at http://www.cabletesting.com/CableTesting/Testing/Definitions/Definitions_Wiremap.htm Category is a proposed standard for a fully shielded, 4-pair cabling system with transmission specifications referenced to 600MHz The cable end interface will probably be something other than the familiar RJ45 connector, mainly to differentiate the Category installation from existing lowerbandwidth infrastructure Because of the higher costs associated with manufacturing and installing these shielded products, their scope of usability is extremely limited in North America (