IBDN System Design and Applications

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IBDN System Design Information IBDN SYSTEM DESIGN INFORMATION •1

To assist designers and planners of Cabling Systems, the

IBDN SYSTEM DESIGN INFORMATION

following chapter provides Design and Application information for IBDN Systems capable of supporting voice, data, LANs, imaging and video services.

Introduction

Implementing IBDN depends on the telecommunications services to be provided, the building architecture and its dimensions.

If you require more information, contact a NORDX/CDT IBDN Certified System Vendor (CSV) in your area. CSV information can be obtained by calling NORDX/CDT at 1-800-262-9334 or by visiting our web site at www.nordx.com.

IN THIS CHAPTER YOU WILL FIND: • IBDN Design Information • IBDN System Matrix • Cat 6 versus Cat 5e • What is performance guaranteed? This information is current at time of printing and is intended for informational purposes only. NORDX/CDT, its affiliates and parent companies accept no responsibility for this information as it is subject to change. In no event shall NORDX/CDT, its affiliates and parent companies be liable for loss of profits or revenues, loss of use of the products or loss of any associated equipment, cost of capital, cost of substitute goods, facilities, services or for any other economic losses or any special, consequential, indirect or exemplary (punitive) damages.

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

The following information has been provided to plan and design IBDN networks ranging from pure copper to copper-optical fiber and all optical fiber. The networks addressed range in scope from single building to multibuilding campus environments. This guide recommends layouts and distances. It specifies the media and components required for implementing copper, copper-fiber networks and all fibers networks. Networks designed according to this guide and in conjunction with appropriate application guidelines, can be assured of system compatibility and performance. The recommendations are based on proven and tested components and system characteristics.

Backbone Cabling The backbone cabling is the portion of the IBDN Cabling System that links the cross-connects within a building and between buildings in a campus environment. The backbone cabling consists of the feeder field of the horizontal cross-connect, intrabuilding and interbuilding backbone cable, and intermediate and main cross-connects. Copper backbone cabling is used for voice and data applications while optical fiber backbone cabling is used for data application where the reach or data rate of copper backbone cabling is exceeded.

STANDARDS The IBDN Structured Cabling System complies with applicable technical standards that address building cabling for telecommunications products and services. Refer to Chapter 1 for summary information regarding Telecommunications Infrastructure Standards. IBDN OVERVIEW IBDN is a structured cabling system that interconnects telecommunications equipment for voice, data and video in a multi-product multi-vendor environment. IBDN is based on modular sub-systems that are independent, yet complementary. This approach facilitates growth, as changes in one sub-system do not affect the others. IBDN network approach uses a hierarchy of nodes and links laid out in a physical star topology. This facilitates moves, additions and changes with virtually no network downtime. IBDN comprises four major sub-systems. The location of each system is shown in figure 1. The following is a brief description of these sub-systems: Equipment Cabling Equipment cabling consists of the cable between the equipment fields of the horizontal, intermediate and main cross-connects and the equipment itself. Examples of the equipment connected with equipment cabling are hubs, switches, servers, and mainframes for data applications, private branch exchanges (PBXs) for voice applications, and controllers for control applications. Equipment cable is typically factory terminated with the appropriate connector(s).

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Figure 1: IBDN Major Sub-Systems

Horizontal Cabling The horizontal cabling is the portion of the IBDN Cabling System, which links the work area cabling to the backbone cabling. The horizontal cabling consists of the telecommunications outlet or MUTOA, the horizontal cable, consolidation point, if used, the distribution field of the horizontal cross-connect, and patch cords or cross-connect wire connected to the distribution field of the horizontal cross-connect. Work Area Cabling The work area cabling consists of work area cables (modular cords) which are used to connect a customer terminal, PC or workstation to the telecommunications outlet or multi-user telecommunications outlet assembly (MUTOA). Also included as part of the work area cabling are baluns or appropriate terminal adapters, which may be required for some legacy data applications. Modular cords are used to interconnect the telecommunications outlet and the terminal equipment. Baluns or appropriate terminal adapters may be included, depending on the data equipment. Optical fiber cords and outlets are used when deploying fiber to the desk.

IBDN System Design Information IBDN PLANNING CONSIDERATIONS This section focuses on key factors that must be considered in order to realize an effective customer premises distribution network design. These include all the components required for the different cabling sub-systems as described in the introduction. ENTRANCE FACILITIES The entrance facility is the interface between the outside plant and the inside building network. The entrance facility is the location where copper cables and/or optical fiber cables entering the building are terminated. Electrical protection should be provided for copper conductors and should be located in the Entrance Facilities. The electrical protection shall adhere to all applicable codes.

Entrance Facility Site Consideration When selecting the entrance facility site location, the on-site location of electricity, water, gas and other utilities should be considered. Entrance Facility Protection In a campus environment, the entrance terminal provides a “straight-through” termination point between intrabuilding backbone cable and interbuilding backbone cable or outside plant cable. The maximum length of unlisted interbuilding backbone cable within a building may differ from regions; it is advisable to refer to the local fire regulations. For example, in Canada the maximum length of unlisted cable within a building is 3 m (10 ft.) and in the United States, it is 15 m (50 ft.).

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IBDN SYSTEM DESIGN INFORMATION

Interbuilding loose tube optical fiber cables are typically unlisted, thereby necessitating being spliced to a listed cable when being placed indoors. However, IBDN does offer an indoor/outdoor loose tube optical fiber cable, which can be placed inside a building thereby eliminating the need for this splice. Interbuilding optical fiber cables do not require protection hardware. Interbuilding outside plant copper cable can be utilized, with appropriate protection, as long as the total cable length does not exceed the maximum distance allowable for the application.

Figure 2: Entrance Facilities

All copper cables entering the building should be electrically protected. These electrical protection systems are mainly classified into two categories, over voltage protection and current limiter. These devices protect people and property from foreign voltages and current. Electrical protection devices are typically installed at the service entrance of a building and shall comply with the standard ANSI/TIA/EIA-607 (CSA T527).

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

EQUIPMENT ROOM The equipment room is the centralized location for the PBX, mainframe computer, and all the telecommunications equipment common to the occupants of the building. The main cross-connect is generally located in the equipment room, or adjacent to it. The main cross-connect is the primary node of a building distribution network and is the cross-connection point for all in-building cables, PABX, connection to telephone company interfaces, and mainframe computers. In a campus environment, the main cross-connect should be contained in one building and an intermediate cross-connect in each of the other buildings in order to maintain the star topology of the IBDN network. If necessary, a main and intermediate cross-connect can be provided to each tenant in a multi-tenant environment.

Equipment Room Size The equipment room should be sized to meet present and future requirements for cabling and equipment. The minimum size of the equipment room should be 14 m2 (150 ft.2).

Equipment Room Site Consideration The following considerations should be taken into account when selecting the location for the equipment room:

Main Cross-Connect Hardware Selection Depending on the number of cables to be terminated at the main cross-connect, the cross-connection hardware can be wall, rack or frame-mounted.

• Accessibility for the delivery of large equipment • Expansion of the equipment room should not be restricted by building components such as elevators, outside or other fixed walls, and so forth • The location of the equipment room should not be below the water level, unless preventive measures against water infiltration are employed • The equipment room should be located away from electrical power supply transformers, motors and generators, X-ray equipment, radio and radar transmitters, and other sources of electromagnetic interference • It is desirable to locate the main cross-connect in or as close as possible to the equipment room. • Access to the ER shall be provided by a door with a minimum size of 910 mm (36 in) wide and 2 m (7 ft) high.

Figure 3: Equipment Room

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Equipment Cable Depending on the data equipment, the appropriate copper or fiber cable should be used and should be terminated at the main cross-connect. The cable length between the equipment and the main or intermediate cross-connect should not exceed 30 m (100 ft.). Cross-Connect Wire and Patch Cord Cable In the main and intermediate cross-connects wire and patch cord length should not exceed 20 m (60 ft.).

The GigaBIX or BIX Cross-Connect System is recommended to terminate all riser UTP cable pairs from PBX, computer room, etc. Depending on the number of copper pairs to be terminated on the main cross-connect, the cross-connection hardware can be wall-mounted or rack-mounted. The recommended cross-connect system for optical fiber system is the FiberExpress series of fiber patch panels. The FiberExpress 4U patch panel can be rack-mounted using a maximum of 4 units of space on a 7 ft. rack or 178 mm (7 in.) when mounted on a wall. If the number of terminating fibers exceeds 480 then a frame-mounted FiberExpress Manager installation is recommended. An optical fiber cross-connect should be designed for terminating at least a 12-fiber optical fiber cable for every telecommunications room in the building.

IBDN System Design Information IN-BUILDING BACKBONE CABLING The in-building backbone cabling consists of multi-pair copper or optical fiber cables and their supporting hardware. It is used to link the main cross-connect to every horizontal cross-connect using a star topology.

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IBDN SYSTEM DESIGN INFORMATION

Figure 5:Various Backbone Termination Points * The distance between the entrance point and the main cross-connect shall be included in the total distance calculations

Media Type UTP (Data)

Figure 4: Backbone Cabling

In-building Backbone Cabling Considerations Separate backbone cables are recommended for voice and data for operational, administrative and maintenance reasons. For voice backbone, a 1:2 ratio of the number of pairs for the horizontal cabling plus an additional 25% allocated for growth should be acceptable. For example, the recommended backbone cable for a telecommunications room serving 100 voice outlets would be a 250 pair cable (100 outlets x 1 pair required/outlet x 2 backbone pairs/pair required + 25% = 250 pairs). For full flexibility, a 1:1 ratio number of pairs of the backbone cabling and number of pairs for the horizontal cabling is recommended. Maximum backbone distances for each media from various points are shown in Table 1.

A 90 m (295 ft.) UTP (Voice) 800 m (2 624 ft.) Multimode fiber*** (62.5/125 µm 2 000 m or 50/125 µm) (6 560 ft.) Singlemode*** 3 000 m fiber (9 840 ft.)

B N/A**

C N/A**

300 m 500 m (984 ft.) (1 640 ft.) 300 m 1 700 m (984 ft.) (5 576 ft.) 300 m 2 700 m (984 ft.) (8 856 ft.)

Table 1: Maximum Distances for Various Media ** No intermediate cross connects are allowed. *** Applications limited

For a data backbone, it depends upon the system to be installed. If the application required high data rates, a minimum of 2 UTP cables such as the cable series 1200, 2400 or 4800LX, is recommended only when the backbones channel length between two actives equipment is less than 100 m (328 ft). If the backbone channel length is greater than 100 m (328 ft), optical fiber cable is recommended for the backbone needs. When optical fiber backbone is used, plan for a minimum 12-fiber optical fiber cable for each telecommunications room. Typically, the minimum allocation of optical fibers is as follows: 4 optical fibers for LANs, 4 optical fibers for redundancy and 4 spare optical fibers for growth.

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

For new installations, NORDX/CDT recommends the use of the “850 nm Laser-Optimized 50/125 µm” multimode fiber (NORDX/CDT’s FX2000). This optical fiber system will provide additional flexibility for current and future applications.

TELECOMMUNICATIONS ROOM The telecommunications room houses cross-connect and interconnect hardware to provide circuit connection and administration between backbone cabling and horizontal cabling.

Optical fiber cables are available with different sheaths for indoor (in-building) and outdoor (inter-building) applications. Backbone optical fiber cable consists of optical fibers with individually colored buffer jackets of flame-retardant polymer. The cable shall be stranded around a central strength member providing a rugged, flexible cable, easy to pull through conduit.

Electronic equipment such as LAN hubs can be placed in the telecommunications room, but should serve only the area covered by the telecommunications room.

The total channel budget loss of the optical fiber backbone link should not exceed the maximum requirement depending on the application as per ANSI/TIA/EIA-568-B.1. When shielded backbone copper cables (i.e., cables with a metallic overall shield), such as the DGR5 or ATMM, are required, grounding of the metal shield must be done at both ends of every backbone cable, with a number 6 AWG ground wire cable. Proper grounding and bonding are essential and reference should be made to ANSI/TIA/EIA-607 (CSA T-527). The backbone cables shall be attached using suitable clamps or grips at a maximum span of 15 m (49 ft.). The maximum recommended conduit fill for backbone cables is 53% for one cable, 31% fill for two cables and 40% fill for three or more cables. The minimum bend radius of a conduit should be based on the minimum bend radius of the cable that will be installed in the conduit. A unique identifier should be assigned to each backbone cable and should be marked on each end. Reference should be made with the ANSI/TIA/EIA-606-A standard. Backbone systems must comply with building, electrical, fire rating, and all other applicable codes. All pathways shall be fire stopped according to applicable codes.

Figure 6:Telecommunications Room

Telecommunications Room Site Considerations Each floor should have a minimum of one telecommunications room. Additional rooms should be provided when the total floor area to be served exceeds 1 000 m2 (10 000 ft.2) or if the maximum horizontal cable run exceeds 90 m (295 ft.). Telecommunications Room Size and Spacing Recommended telecommunications room sizes for various serving areas are shown in Table 2. Serving Area (m2) (ft.2) 1 000 10 000 800 8 000 500 5 000

Room Size (m) (ft.) 3 x 3.4 10 x 11 3 x 2.8 10 x 9 3 x 2.2 10 x 7

Table 2:Telecommunications Room Size Recommendations

Pulling tension for 22, 24 and 26 AWG copper backbone cables shall be respected.

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IBDN System Design Information Rooms should have sufficient space to accommodate two 475 mm (19 in.) relay racks for mounting electronic equipment, fiber patch panel, and other components. The equipment can be wall-mounted or rack-mounted. Electronic telecommunications equipment should be rack-mounted. A minimum of two walls shall be covered with 20 mm (3/4 in.) plywood, 2.44 m (8 ft.) high, rigidly fixed and capable of supporting attached equipment. False ceilings shall not be used. Access to the TR shall be provided by a door with a minimum size of 910 mm (36 in.) wide and 2 m (7 ft.) high. A minimum of 2 duplex 110 volts AC power outlets with U-grounded receptacles and separately fused at 15 amperes (2 duplex 220 volts AC 13 amperes for European applications) shall be provided. For telecommunications grounding, the requirements of ANSI/TIA/EIA-607 (CSA T527) should be followed. HORIZONTAL CABLING Horizontal cabling links the distribution field in the telecommunications rooms to the outlets in the work areas. The maximum horizontal distribution length shall not exceed the 90 m (295 ft.) limit. If there is a need to go beyond the 90 m (295 ft.) limit, there must be a provision for additional telecommunications rooms on the floor.

Horizontal Cabling Recommendations The sharing of cable sheath for different or same applications on 4 pair Horizontal Cabling is not recommended. It is recommended to provide horizontal cables to accommodate the maximum capacity of the floor size. This design will facilitate easy moves, additions and changes (without additional costs for re-cabling). It is recommended to provide the same number of horizontal cables to each work area.

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IBDN SYSTEM DESIGN INFORMATION

It is recommended to provide a minimum of two horizontal cables per work area to meet today’s and future service needs. • One telecommunications outlet/connector shall be a 4pair, 100 Ω UTP cable, Category 3 or higher (Category 5e recommended) • The other/second telecommunications outlet/connector shall be one of these 2 proposed horizontal media: - 4-pair, 100 Ω UTP cable, Category 5e cable or - 2 multimode optical fibers either 62.5/125 µm, 50/125 µm or 850 nm Laser-Optimized 50/125 µm. A unique identifier shall be assigned to each horizontal cable and shall be marked on each end. Reference should be made with the ANSI/TIA/EIA-606-A standard.

Figure 7: Horizontal Cabling

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

Horizontal Copper Cabling Considerations The high data transmission rates over UTP cable are possible through advances in cable manufacturing pioneered by NORDX/CDT. These cables have low attenuation and high noise immunity, the necessary conditions for highspeed transmission of data signals. Transmission of high speed data signals requires many other components besides the high performance horizontal cable, such as the cross-connect system, modular cords and telecommunications outlets. These components also play a critical role in high speed data transmission. Traditionally, the above connection components were not considered as critical factors in total system performance. This point of view has changed with the emergence of high speed LANs. The performance of the connection hardware must match the performance requirements of the horizontal cable. For successful transmission of high speed signals over data grade UTP, end-to-end NORDX/CDT components are recommanded. Interaction between components is critical, more so with category 6 cabling systems. These components should be qualified to ensure satisfactory channel performance. Horizontal cabling is meant to support high speed data rates, making it imperative that proper installation procedures be followed. All IBDN CSVs are properly trained to ensure IBDN System Performance. Examples of some of these procedures are listed: • All components must be manufactured by NORDX/CDT • When installing cable, ensure UTP separation guidelines for EMI sources are met • The total length of equipment cords, patch cords and cross-connect wire shall not exceed 10 m (33 ft.) • In order to reduce the effect of multiple connections in close proximity on NEXT it is recommended that the consolidation point be located at least 15 m (49 ft.) from the telecommunications room and 5 m (16 ft.) for the telecommunications outlet • The amount of untwisting of horizontal cables for termination purposes (at the patch panel and at the telecommunications outlet) shall not be greater than 13 mm (0.5 in.) • The amount of untwisting of cross-connect wire, for termination purposes at the BIX Cross-Connect System should not be greater than 13 mm (0.5 in.) • The pulling tension for one set of 4 pair (24 AWG) horizontal cables should not exceed 110 N (25 lbf) to avoid stretching the conductor during installation

• Cross-connect wires, patch cords and horizontal cables must be routed and dressed in a loose manner. Tightly wrapping or lacing the wires or cables may degrade performance • Telecommunications outlets in the work area should have 8 position jacks and the ANSI/TIA/EIA-568-B (T568A-ISDN or T568B-ALT) standard compatible pin configuration. The use of end-to-end NORDX/CDT components for all horizontal and backbone cabling along with proper planning and installation ensures certified system performances. Copper Cable Installation Considerations One of the important criteria for a copper cable installation is adequate spacing between EMI (Electro-Magnetic Interference) sources and copper cables, and especially for high-speed data systems. Table 3 gives the minimum recommended separations between the various EMI sources and copper cables. Grounded metal conduits or pathways provide adequate protection from electrical noise sources. Open or non-metal pathways (plastic wireways) should be placed with sufficient separation from noise sources and as close as possible to a ground plane (building metal structure), or alternatively a grounded metal separator can be placed between sections. Conditions

Minimum Separation Distance (5 kVA)

Unshielded power lines or electrical equipment in proximity to open or non-metal pathway Unshielded power lines or electrical equipment in proximity to a grounded metal conduit pathway Power lines enclosed in a grounded metal conduit (or equivalent shielding) in proximity to a grounded metal conduit pathway Fluorescent lighting

127 mm (5 in.)

305 mm (12 in.)

610 mm (24 in.)

64 mm (2.5 in.)

152 mm (6 in.)

305 mm (12 in.)

—

76 mm (3 in.)

152 mm (6 in.)

305 mm (12 in.)

Table 3: Minimum Separation Distance Between EMI Sources and UTP Medium

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IBDN System Design Information When using divided raceways (one section for power, one section for telecommunications), it is important to twist together loose power wires in the power section of the raceway. Similar precautions should be taken for modular furniture raceways. For additional details on calculation, refer to the IBDN Design Guide.

CENTRALIZED OPTICAL FIBER CABLING SYSTEM The ANSI/TIA/EIS-568-B.1 proposes fiber-to-the-desk cabling system utilizing centralized electronics versus the traditional method of distributing the electronics to the individual floors. It provides assistance in the planning of a fiberto-the-desk system.

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IBDN SYSTEM DESIGN INFORMATION

Horizontal Optical Fiber Cabling Considerations For horizontal distribution, a minimum of a two-fiber 62.5/125 µm, 50/125 µm or 850 nm Laser-Optimized 50/125 µm optical fiber cable is required. Additional optical fibers should be considered for redundancy. SC duplex connectors and adapters are recommended for all new installations of optical fiber LAN networks. Existing optical fiber LAN networks, which have an installed base of ST compatible connectors and adapters, may continue to use the same type of connectors and adapters for both existing and future additions. A MT-RJ solution is recognized for new installation (for design concerns, contact a NORDX/CDT IBDN Certified System Vendor of your area). Optical Fiber Cable Installation Considerations Do not exceed the minimum bend radius of the optical fiber cable, which is typically 20 times the cable diameter during installation and 10 times the diameter of the cable at rest. Do not exceed the maximum pulling tension for the cable. Although excess pulling may not actually break the optical fiber, it can increase the optical fiber attenuation such that the installed system may not operate within the designed limits. Keep the cable runs short, and minimize the number of bends. Where possible, avoid placing cable directly against rough surfaces such as concrete, stones or brick. Sleeves should be used when running through walls or floors. Cables installed in access floors may be placed in a conduit. Placing optical fiber cable in conduit is similar to that of copper cable. In a suspended ceiling, optical fiber cable can be run in one of two ways: inside conduit or exposed, depending on the applicable local codes.

Figure 8: Centralized Optical Fiber Cabling

Work area connections are extended to the main cross-connect by utilizing either pull-through cables, an interconnect or a splice in the telecommunications room. The maximum horizontal cabling length is specified at 90 m (295 ft). The distance of horizontal and backbone cabling combined with work area and cross-connect patch cords is not to exceed 300 m (984 ft). By adhering to the 300 m (984 ft), the multimode cabling system will support future multi-gigabit applications (note: cable length is dependent on the fiber type and the application). Centralized Cabling Systems shall be located within the same building of the work areas being served. All ‘move and change’ activity shall be performed at the main crossconnect. Horizontal links should be added and removed in the telecommunications room. When using the pull-through method, the cable has a continuous sheath from the work area through the telecommunications room to the centralized cross-connect. The pull-through cable length with the service loop shall be limited to 300 m (984 ft.). When designing a Centralized Cabling System, provisions shall be made to allow for the migration from pullthrough, interconnect or splice to a cross-connect implementation.

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

To facilitate this migration, sufficient space shall be left in the telecommunications room for additional patch panels. In addition, adequate cable slack shall be left in the telecommunications room to allow for the cables to be moved to the cross-connect or interconnect location. The cable slack shall to be included in the maximum 300 m (984 ft.) cable length allowed. Fibers can be joined by either using re-mateable connectors or splices. If connectors are used, the connector shall be the SC duplex, ST-Compatible or MT-RJ. Fibers may be fusion or mechanically spliced, provided the requirements as specified in ANSI/TIA/EIA-568-B.3 are met. Horizontal Cabling for Open Offices A horizontal cabling termination point (multi-user telecommunications outlet assembly) and/or intermediate horizontal cabling interconnection point (consolidation point) provide more flexibility in open office layouts with modular furniture, where frequent office rearrangements are performed. Both the multi-user telecommunications outlet assembly (MUTOA) and the consolidation point shall be located in a fully accessible, permanent location. Both solutions can be used in a copper cabling system and/or optical fiber system. Multi-User Telecommunications Outlet Assembly The multi-user telecommunications outlet assembly (MUTOA) is a termination point for the horizontal cabling consisting of several telecommunications outlets in a common location. The modular cord extends from the MUTOA to the terminal equipment without any additional intermediate connections. This configuration allows the open office plan to change without affecting the horizontal cabling.

Figure 9: Multi-user Telecommunications Outlet Assembly

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The following guidelines should be followed when installing a MUTOA assembly • The MUTOA should not be installed in a ceiling • The MUTOA should be accessible by the end-user at all times • The maximum modular cord length should be 20 m (66 ft.) • The modular cord connecting the MUTOA to the terminal equipment shall be labeled on both ends with a unique identifier • The MUTOA shall be marked with the maximum allowable work area cabling (modular cord) length as per the following table:

A Meters (feet) 5 (16) 5 (16) 5 (16) 5 (16) 5 (16)

B Meters (feet) 90 (295) 85 (279) 80 (262) 75 (246) 70 (230)

C Meters (feet) 5 (16) 9 (30) 13 (44) 17 (57) 22 (72)

Total Channel Length Meters (feet) 100 (328) 99 (325) 98 (322) 97 (319) 97 (319)

Table 4: Horizontal and Work Area Cabling Lengths

IBDN System Design Information Consolidation Point The consolidation point is an interconnection point within the horizontal cabling. The consolidation point performs a “straight-through” intermediate interconnection between the horizontal cabling coming from the horizontal crossconnect and the horizontal cabling going to a MUTOA or the telecommunications outlet in the work area. Cross-connection between these cables is not allowed. A consolidation point may be useful when reconfiguration is frequent, but not so frequent as to require the flexibility of a MUTOA.

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IBDN SYSTEM DESIGN INFORMATION

15 m (50 ft.)

Figure 11:Work Area ≤ 5 m (16 ft.)

≤ 90 m (295 ft.)

≤ 5 m (16 ft.)

Figure 10: Consolidation Point

The following guidelines shall be followed when installing a consolidation point • Ensure that the total channel distance is 100 meters or less • The cables to and from the consolidation point should be securely attached without violating the cables’ minimum bending radius requirements • GigaBIX or BIX mounts should be in enclosures to prevent dust accumulation and also to provide strain relief and mechanical protection for the incoming and outgoing cables • Ensure there is about 150 mm (6 in.) of cable slack in the enclosure for future reconnections • Special care shall be taken to ensure that the enclosures are installed according to applicable codes • It is recommended that the consolidation point be located at least 15 m (50 ft.) from the telecommunications room in order to avoid additional NEXT due to short link resonance of multiple connections in close proximity • No more than one consolidation point and one MUTOA shall be used within the same horizontal run.

An 8-position T568A-ISDN wired modular jack (ISO 8877) is recommended for each voice and data application. If an optical fiber cabling system is installed, NORDX/CDT recommends the SC duplex connectors. It will provide the capability of interfacing with LAN devices, and complies with ANSI/TIA/EIA-568-B.1. When necessary, the ST-Compatible connector will be accepted and the small form factor connectors e.g. LC, MT-RJ will be recognized. The faceplates can accommodate up to 6 modules using a 2 in. x 4 in. electrical wall box with single gang plastering (a 4 in. x 4 in. wall box is recommended for the purpose of slack storage) and up to 12 modules using a 4 in. x 4 in. electrical wall box with double gang plastering.

WORK AREA The work area includes telecommunications outlets, modular cords, media conversion devices, such as baluns, adapters and NIC (Network Interface Cards). The NIC cards allow PCs & workstations to interface to the LAN. Normally NIC cards have an 8-position modular jack interface to attach to a work area system. Telecommunications Outlet The telecommunications outlet is an interface between the horizontal cabling and the modular cord. When a copper horizontal cabling system is installed, an 8-position modular jack (T568A-ISDN) provides the capability of interfacing with various discrete data and LAN stations, and complies with ANSI/TIA/EIA-568-B.1.

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IBDN System Design Information •2

IBDN SYSTEM DESIGN INFORMATION

Telecommunications Outlet Cabling The 8-position modular jack outlet should be wired according to T568A-ISDN or T568B-ALT. Table 5 gives the horizontal cable pair arrangements with the modular jack. PIN Number 1 2 3 4 5 6 7 8

T568A White-green Green-white White-orange Blue-white White-blue Orange-white White-brown Brown-white

T568B White-orange Orange-white White-green Blue-white White-blue Green-white White-brown Brown-white

Table 5:Telecommunications Outlet Pin/Pair Designation

BALUNS If required, baluns and adapters can be used in conjunction with a modular cord to connect a workstation to a telecommunications outlet. Baluns are used for converting an unbalanced transmission on a coax medium to a balanced transmission on UTP cable. Adapters convert different types of connectors such as DB9, DB25, etc. to an 8-position modular connector (T568-A-ASDN or T568-ALT). CROSS-CONNECT/INTERCONNECT SYSTEM IBDN offers the following copper and optical fiber cross-connect/interconnect systems which provide the designer with the flexibility to select the most appropriate system for the application and size of the installation: UTP Cross-Connect/Interconnect Systems:

Modular Cord Four-pair UTP modular cords with T568A-ISDN pin assignment are recommended. For voice and data applications, modular cords must be twisted pair, solid or stranded. Termination resistors used for ISDN must be terminals external to the telecommunications outlet. Modular cords are available in solid and stranded. Stranded modular patch cords are typically used where flexibility is a major requirement (e.g. cross-connect point). They can be used for voice as well as for data applications. Modular cords are optimized to provide enhanced electrical characteristics necessary to ensure reliable operation for high speed LANs.

• • • • • •

It is recommended that all modular cable be factory terminated with the appropriate connector(s), to ensure that electrical and mechanical requirements are met. Field termination of modular cable is not recommended because it is impossible to achieve the same conditions as in the factory, test equipment to verify the electrical and mechanical requirements is not available in the field, and labor costs to manually terminate the conductors in the connector are more expensive than automated factory termination costs.

Wall mount and frame mount systems are primarily used to form the main cross-connect because they provide flexibility for large installations while rack mount systems are primarily used to form the horizontal cross-connect because they provide good flexibility for small to medium installations.

OPTICAL FIBER PATCH CORDS A fiber patch cord assembly consists of a length of breakout or zip cord cable equipped with a factory installed connector on each end. Factory made optical fiber patch cords will provide a low insertion loss and high repeatability values since the assemblies are tested as per industry standards requirements, which is not always the case with field made optical fiber patch cords. NOTE: It is important to be consistent in the choice of the optical fiber cable type for the patch cords, it should always be the same type and performance as the horizontal or backbone optical fiber cable to avoid additional attenuation losses (e.g. a 62.5/125 µm cable and a 62.5/125 µm patch cord within the same channel).

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Wall Mount GigaBIX System Wall Mount BIX System Wall Mount BIX Modular Jack System Wall Mount 110 System Rack Mount Patch Panel System Frame Mount BIX System

Optical Fiber Cross-Connect/Interconnect Systems:

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Wall Mount FiberExpress System Rack Mount FiberExpress System Rack Mount FiberExpress Bar System Frame Mount FiberExpress Manager System

Summary IBDN Structured Cabling Systems are easy to design and install. Their security and versatility make them integral to any building network. For more design or installation information, contact a NORDX Certified System Vendor (CSV) in your area. For CSV information contact NORDX/CDT customer services or visit our web site at www.nordx.com.

IBDN Systems Matrix IBDN is a comprehensive system of quality products, •3

design guidelines and installation practices backed by a

IBDN SYSTEMS MATRIX

certification process. (See section 2 for information on IBDN Certification).The following pages provide detailed product information of the components required for the various IBDN Systems available.

This information is current at time of printing and is intended for informational purposes only. NORDX/CDT, its affiliates and parent companies accept no responsibility for this information as it is subject to change.

In no event shall NORDX/CDT, its affiliates and parent companies be liable for loss of profits or revenues, loss of use of the products or loss of any associated equipment, cost of capital, cost of substitute goods, facilities, services or for any other economic losses or any special, consequential, indirect or exemplary (punitive) damages.

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IBDN Systems Matrix •3

IBDN SYSTEMS MATRIX

NORDX/CDT’s IBDN Gigabit Cabling Solutions provide you with a choice of three end-to-end cabling systems that are optimized for the gigabit-networking era. Whether your needs call for our 4.8, 2.4 or 1.2 Gigabit System, you can be assured that the selection of a Certified IBDN Gigabit Cabling System will provide the capacity and performance to maximize your overall IT strategy now and in the future. Take the risk out of your decisions with an IBDN Certified Gigabit Cabling System that provides guaranteed channel performance, standards compliance and is ‘‘Certified for What’s Coming Next.”

IBDN Gigabit Cabling Solutions IBDN Solutions

Telecom Room

Work Area Outlets

Available

(Connectors -

UTP

IBDN

Channel

Guaranteed

Channel Std

Systems

Bandwidth

Data Rate

Compliance

IBDN

160 MHz

1.2 Gb/s

Cat. 5e *

GigaFlex 1200

PowerSum

TIA/EIA IEEE Gigabit

Backbone Cable

Cross-Connect

Cross-Connect

Hardware

Patch System

Horizontal Cable

Faceplates &

Modular

Adapters)

Cords

IBDN GigaFlex 1212 4-pair (CMR) GigaBIX Cross-Connect System

GigaBIX Cross-Connect Wire IBDN GigaFlex 1212 4 -pair (CMR) PS5E BIX DVO Outlet

IBDN GigaFlex 1213 4-pair (CMP)

GigaBIX Patch Cords

IBDN GigaFlex 1213 4-pair (CMP) EZ-MDVO PS5E Module

PS5E Modular Cords

IBDN GigaFlex 1224 4-pair (LSOH) GigaFlex PS5E Module

IBDN GigaFlex 1224 4-pair (LSOH) PS5E BIX Patch Panel PS5E HD-BIX Patch Panel

MediaFlex Outlets

PS5E HD-110 Patch Panel

Interface Plates

Flex Patch Panel/EZ-MDVO PS5E Module

MDVO Faceplates

Flex Patch Panel/GigaFlex PS5E Module

MDVO Adapters

PS5E Modular Cords

European Style Faceplates French Style Faceplates 110 Cross-Connect System

IBDN

250 MHz

GigaFlex 2400

PowerSum

2.4 Gb/s

Cat. 6 **

PS5E 110 Patch Cords

IBDN GigaFlex 2412 4-pair (CMR) GigaBIX Cross-Connect System

GigaBIX Cross-Connect Wire IBDN GigaFlex 2412 4-pair (CMR) GigaFlex PS6+ Module

TIA/EIA

IBDN GigaFlex 2413 4-pair (CMP)

GigaBIX Patch Cords

IBDN GigaFlex 2413 4-pair (CMP) MediaFlex Outlets

ISO/IEC

IBDN GigaFlex 2424 4-pair (LSOH) Flex Patch Panel/GigaFlex PS6+ Module

PS6 Modular Cords

IBDN GigaFlex 2424 4-pair (LSOH) Interface Plates

IEEE Gigabit

PS6 Modular Cords

MDVO Faceplates

GigaFlex PS6+ Patch Panel

MDVO Adapters European Style Faceplates French Style Faceplates

IBDN

300 MHz

GigaFlex 4800LX

PowerSum

4.8 Gb/s

Beyond Cat. 6**

IBDN GigaFlex 4812 4-pair (CMR) GigaBIX Cross-Connect System

GigaBIX Cross-Connect Wire IBDN GigaFlex 4812 4-pair (CMR) GigaFlex PS6+ Module

TIA/EIA

IBDN GigaFlex 4813 4-pair (CMP)

GigaBIX Patch Cords

IBDN GigaFlex 4813 4-pair (CMP) MediaFlex Outlets

ISO/IEC

IBDN GigaFlex 4824 4-pair (LSOH) Flex Patch Panel/GigaFlex PS6+ Module

PS6 Modular Cords

IBDN GigaFlex 4824 4-pair (LSOH) Interface Plates

IEEE Gigabit

GigaFlex PS6+ Patch Panel

MDVO Faceplates MDVO Adapters European Style Faceplates French Style Faceplates

* ANSI/TIA/EIA-568-B.1 ** TIA/EIA Final Cat 6 – June 2002 ISO / IEC JTC1/SC 25/WG 3 N696 – April 2001 Notes: Backbone can be configured with IBDN Optical Fiber Cable PS Cross-Connect Wire, renamed GigaBIX Cross-Connect Wire GigaFlex PS5E Modules are available only in some markets

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PS6 Modular Cords

IBDN Systems Matrix From modular cords and cables to workstation outlets that complement the FiberExpress System, we offer a full range of fiber optic linking cords in either multimode (62.5 µm, 50 µm and 850 nm laser-optimized 50 µm) or singlemode, in standard or custom lengths, and all with a variety of connectors. Multifiber ribbon cables (6 or 12) are also available in standard or custom lengths, tested and pre-terminated with MPO connectors. With a great selection of outlets, patch panels and connecting hardware, our products remain at the industry’s forefront because they are designed to give you the flexibility you need to meet the technological challenges and demanding requirements of your particular working environment.

•3

IBDN SYSTEMS MATRIX

FIBER CHANNEL TOPOLOGIES

IBDN FIBEREXPRESS SYSTEM MATRIX

Fiber Channel Solution

Fiber-to-the-Desk (FTTD) and and Centralized Fiber

Fiber Backbone (in-building)

Fiber Backbone (campus environment)

FiberExpress Preterminated Solutions*

Cables FX300 : 62.5/125 µm Multimode cable FX600 : 50/125 µm Multimode cable FX2000 : “850 nm Laser-Optimized 50/125 µm” Multimode cable Singlemode cable

• Breakout, distribution or interconnect cable series (offered in all Multimode or Singlemode cable)

• Breakout or distribution cable series (offered in all Multimode or Singlemode cable)

• Breakout or distribution cable series indoor, outdoor, indoor/outdoor or armored (offered in all Multimode or Singlemode cable)

• FiberExpress Ribbons cable series (offered in all Multimode or Singlemode cable)

Cross-Connect Hardware in the Telecommunications Room

• FiberExpress Manager • FiberExpress rack mount patch panel

• FiberExpress Manager • FiberExpress rack mount patch panel • FiberExpress wall mount patch panel

• FiberExpress Manager • FiberExpress rack mount patch panel • FiberExpress wall mount patch panel

• FiberExpress Bar • FiberExpress Manager

Patch cords in the Telecommunications Room and at the Work Area

• Fiber Patch Cords: SC, SC Duplex, ST-Compatible, MT-RJ, LC, FC (available with Multimode FX300, FX600, FX2000 or Singlemode cable)

Patch Cords in the Telecommunications Room and at the Work Area Outlets at the Work Area

Outlets at the

• FiberExpress Bar

• MDVO Multimedia Outlet Box • Multi-User Outlet Box Work Area Outlet with • MDVOFlex MDVOFlex Mutlimedia Inserts • Interface Outlet with MDVOFlex Mutlimedia Inserts

Fiber connectivity

Fiber Connectivity

• Optimax2 (SC, ST-Compatible for multimode FX300, FX600 and FX2000) • Epoxy (SC, ST-Compatible for multimode FX300, FX600, FX2000 and Singlemode) • Fiber Pigtails (SC, ST-Compatible, MT-RJ, FC, LC for multimode FX300, FX600, FX2000 and Singlemode)

Optical Fiber Matrix Singlemode UPC fiber optic cable assemblies SC, ST-compatible and FC are Telcordia compliant *FiberExpress Pre-terminated Solutions provide simple-to-install, high-performance fiber channels through custom length, high precision factory terminated cables and matching optical connectivity components.

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Notes •

NOTES

•

Cabling Performance Whether you are a telecommunications consultant, sys•4

tems integrator or end-user, your goal in selecting and

CABLING PERFORMANCE

implementing a structured cabling system is to choose a cabling system that will support both the immediate and future needs of your network and business applications.

In reading magazines, advertisements and brochures from various manufacturers of cabling products, you have been exposed to a wide variety of opinions regarding what are the important issues affecting cabling system performance and which cabling system will best suit your networking infrastructure needs.

In this sub-clause, we will review the next generation Category 6 cabling system, and what makes it different from the performance of existing Category 5 and enhanced Category 5 (Category 5e) systems and we will clarify what is the guaranteed performance of your network.

Our goal is to provide you with a comprehensive understanding of cabling system performance which, in turn, will assist you in achieving your goal of selecting the right cabling system to best meet your current and future networking needs.

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Cabling Parameters and How they Affect Network Performance •4

CABLING PERFORMANCE

INTRODUCTION Your cabling is like a bridge or a roadway to move information between different parts of your network, from a source to a receiver. It is very important that your roadway is constructed on a solid foundation, using high performance matched components, with enough capacity to support today’s and tomorrow’s high speed data applications, and without loss of information. The focus of my paper will be on the next generation Category 6 cabling system, and what makes it different from the performance of existing Category 5 and enhanced Category 5 (Category 5e) systems. The key to unraveling the mystery of cabling and its affect on network performance is to understand what the parameters mean, what is IL (Insertion Loss), ILD (Insertion Loss Deviation), Return Loss and different sources of noise. We will need to understand how these cabling parameters relate to the Signal-to-Noise Ratio (SNR), because that is what really affects network performance. GOING ON A JOURNEY Let us imagine that we are going on a journey and reflect a little bit on what we need to do to prepare for our journey. Just like our life, we have a vision of where we want to be and we rely on our knowledge and on our experience to get to where we’re going. We study what is the best way to get to our destination. We are prepared to meet the challenges along the way and to have the means to accomplish our goals and to realize our vision. It is the same way with your cabling system. It is the roadway for the flow of information in your network. You want to avoid bottlenecks and ensure that the roadway is capable of handling the data flow without loss of information. With all the technical jargon, it is easy to get confused and to lose sight of what is important. Let’s start by looking at all the different cable parameters, what do they mean and how they affect network performance.

All the other cabling parameters can be related to Internal Noise such as Near End and Far end Crosstalk interference or to External Noise such as Alien Crosstalk. A high crosstalk loss in dB means less noise and a cleaner signal. A cleaner signal means fewer bit errors. CHANNEL PERFORMANCE A simple way to look at a Channel is a black box. The channel performance is measured by sending a signal on a pair at one end of a channel and measuring the signal received on the same pair at the opposite end of a channel or another pair at the same end or at the opposite end. These measurements are performed using field test instruments as a function of frequency. For Category 5 or 5e cabling systems the frequency range is from 1 MHz to 100 MHz. For Category 6 systems, it is from 1 MHz to 250 MHz. Lets look at what is inside the black box to determine the Insertion Loss. A Channel is comprised of a series of components. The simplest channel as specified by IEEE (Institute of Electrical and Electronic Engineers) is comprised of a cord and a connector at each end and a length of cable in-between. If we take the specified Insertion Loss of each component, pro-rate it for length and add up these losses, we would expect the result to be the Insertion Loss of the Channel. Is that the Insertion Loss of my channel? Well, not quite. There is an additional loss due to temperature and another additional loss due to component mismatch called ILD. All the component losses in the TIA/EIA-568-B and ISO 11801 cabling standard are specified at 20 °C. If the cable is installed in a higher temperature environment, it is necessary to take this into account. For example, the loss increase for UTP cables is approximately 4 % increase for every 10 °C increase in temperature above 20 °C. The additional loss caused by component Impedance mismatch is explained in Figure 1.

Insertion Loss is the most important parameter. Insertion Loss measures the loss of signal power between the input and the output of a Channel. A low Insertion Loss in dB means a stronger signal. A strong signal means that a Channel is less susceptible to noise in the environment. It also means that a Channel has a higher information capacity. A good analogy is a water pipe, the larger the pipe, the stronger the water pressure (signal power) and the larger the capacity (information flow). Figure 1 - Effect of Component Impedance Mismatch

Return Loss is a measure of the Impedance mismatch between components in a Channel. Ideally all components have a nominal 100 Ω Impedance. In practice they are different due to design, manufacturing and installation variances. A high Return Loss in dB means fewer reflections and well-matched components. Signal reflections are a source of noise that contributes to bit errors for Gigabit Ethernet (1000BASE-T) networks.

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Each component in a channel has a Characteristic Impedance represented by the symbols Z1, Z2, … in the diagram. For ideal components, Z1, Z2, … is 100 Ω and is independent of frequency. In practice, this is not the case. Cable Impedance varies with frequency in a random fashion and sometimes in a periodic fashion because of manufacturing variations and installation effects. Also,

Cabling Parameters and How they Affect Network Performance the Impedance of connecting hardware varies depending on design and the type of compensation circuitry that is used.

the other pin pair assignments (pins 1-2, pins 4-5 and pins 7-8) because the blades at the plug termination are spaced further apart.

Any difference in Impedance along the cable or between components gives rise to a signal reflection. Return Loss is a measure of the amount of signal reflection. The higher the Impedance differences the greater the reflected signal.

The primary contributor to ILD noise at mid frequencies (10 to 30 MHz) is the Impedance mismatch of the cable and the cords. For Category 5 channels, this impedance mismatch can be as high as +/- 15 Ω, whereas for Category 5e channels, the cable - cord mismatch is usually less than + / - 5 Ω and is typically + / - 3 Ω for Category 6 channels.

•4

CABLING PERFORMANCE

Because some of the signal is reflected back to the source, it results in an additional loss called Mismatch Loss. A portion of this reflected signal is also re-reflected back and mixes in with the main signal. This re-reflected signal is a noise source because it is delayed in time and can add or subtract from the main signal. This re-reflected signal is called ILD (Insertion Loss Deviation). WHY IS ILD IMPORTANT? • It is a noise source that contributes to bit errors even when there is no crosstalk noise present, for example when using STP cables. In fact it is much more difficult to maintain tight control of impedance of STP cable because of manufacturing process variations caused by the geometry of the foil tape. • When the ILD peaks occur at or a sub-multiple of the clock frequency, they can cause timing jitter. This timing jitter reduces the noise threshold at the detector and contributes to errors.

A lot ILD noise can be generated for worst-case Category 5 channels when using cords that are not well-matched to the horizontal cables. Cord - cable Impedance mismatch for Category 5 cabling is the dominant contributor to noise and bit errors for Fast Ethernet and Gigabit Ethernet networks. It by far exceeds the noise contribution due to Near End crosstalk at the maximum power frequencies, between 10 - 30 MHz. That is also why minimum Category 5e cabling is recommended for Gigabit Ethernet (1000BASE-T). INTERNAL NOISE The different types of Internal noise sources are illustrated in Figure 3 for a Gigabit Ethernet application which uses all four pairs to send and receive a cumulative data rate of 1000 Mb/s (250 Mb/s over each pair). A hybrid transformer circuit within the transceiver at either end of a channel separates and combines transmit and receive signals onto a single pair, simultaneously.

Figure 2 – Channel Insertion Loss and ILD Figure 2

Figure 2 shows a typical Channel Insertion Loss versus frequency trace on all four pairs (Blue, Orange, Green and Brown) of a 4-pair cable. The roughness in the Insertion Loss trace becomes more apparent at high frequencies. This roughness is caused by an ILD noise signal that is superimposed on top of the Receive signal. The roughness is more apparent at higher frequencies because the Insertion Loss is higher and the signal is weaker. The primary contributor to ILD noise at high frequencies (greater than 100 MHz) is connector Impedance mismatch. In the example of Figure 2, the orange pair shows more roughness (ILD). When we look at how the Orange pair is terminated on the connector, it is terminated on the split pair position (pins 3 - 6). This split pair pin assignment tends to have a higher impedance mismatch than

Figure 3 – Internal Noise Sources for 1000BASE-T

Figure 3

As you can see that Return loss in the channel appears as noise at the Receiver on the bottom right of Figure 3. ILD appears as noise at the Receiver on the bottom left. Each receiver receives the combined Power Sum NEXT from three near end transmitters and the combined Power Sum FEXT from three far end transmitters. Power Sum NEXT is a much stronger noise source than Power Sum FEXT because the Far end noise is attenuated by the Insertion Loss of the cable pair before it reaches the Receiver.

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Cabling Parameters and How they Affect Network Performance •4

CABLING PERFORMANCE

EXTERNAL NOISE Alien Crosstalk is an external noise source that is significant and needs to be considered in determining network performance. Because cables are usually laid in trays or pulled in a conduit, the cables tend to be close to one another. However, the random placement of cables during installation tends to minimize adjacency and proximity for long distances. For Category 6 channels, we have measured the combined Alien Power Sum NEXT to be about the same as the PSNEXT within the cable. Another external noise source that must be considered is the induced noise from power line transients. Based on extensive testing performed in our IBDN laboratories on 100BASE-TX applications we recommend a minimum 50 mm (2 in.) separation between branch power (20 A) circuits and telecommunications cables in plastic (non-metallic) raceways. These tests simulate worst case transients of up to 500 volts for power conductors that are loosely laid in a partitioned furniture raceway. The power line transients are much less for power cables where the conductors are twisted. SIGNAL-TO-NOISE RATIO How do all these cable parameters add up in a worst case Channel configuration. For this purpose, we developed a very detailed channel model that calculates the combined Signal-to-Noise Ratio (SNR) at the Channel output taking all noise sources into account, and not just NEXT. For the model, a spreadsheet was developed that allows the user to input different cabling parameters. For modeling purposes we evaluated the performance of a worst case channel of 100 meters and four connectors (two connectors in the Work Area and two connectors in the Telecommunications Rooms). The model takes into account the channel configuration, the lengths of cords and cables, the temperature of the cable, the PSNEXT, PSFEXT and Return Loss of components and the Alien NEXT. The ILD noise is calculated automatically from the Return Loss of the components. The key result is the Signal-to-Noise Ratio (SNR) at the output of the Channel. A positive SNR value implies that the Bandwidth is met at the test frequency. Figure 4 shows in graphical form the Signal and the Noise for a minimally compliant Category 6 Channel compared to a Category 5e Channel at 100 MHz. The relative magnitudes of the noise sources are shown in purple as well as the combined Noise. The combined Noise includes Alien NEXT, ILD Noise, PSFEXT and PSNEXT. The Signal and the Noise levels are expressed in dB and are shown as a percentage of the Transmit signal level in the table below the graph. What counts is the difference between the Receive signal level compared to the combined Noise level. An easier way to look at this difference is in decibels because the percentage values are quite small.

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At 100 MHz the SNR for Category 6 Channel is 14.2 dB compared to 2.8 dB for a Category 5e Channel.

Figure 4 – Signal and Noise for Categoy 6 and Category 5e at 100 MHz

WHAT IS THE EFFECT OF CABLE TEMPERATURE? The effect of temperature on the Signal-to-Noise Ratio is shown in Table 1. When the temperature is increased to 40 °C (realistic case) or 60 °C (pessimistic case), the SNR is -1.1 dB and - 2.9 dB respectively. A field test instrument would indicate a test failure for these conditions because the Insertion Loss headroom is negative.

Table 1 – Effect of Cable Temperature on Insertion Loss and SNR

What is the solution. The draft TIA standard says that for high temperature environments, the cable length is derated. For example, at 40 °C the length de-rating is 6 meters for a maximum cable length of 84 meters instead of 90 meters. A better solution would be to use a cable such as an IBDN 4800LX cable that has low Insertion Loss and doesn’t need to be de-rated.

Cabling Parameters and How they Affect Network Performance WHAT IS THE EFFECT OF ALIEN NEXT ON A CATEGORY 6 CHANNEL? Alien NEXT is specified for Category 5e or Category 6 bundled cable assemblies. Special designs are required for bundled cable assemblies to meet the tight performance requirements of TIA/EIA-568-B.2 standard. The Power Sum Alien NEXT from all surrounding cables in the bundle must be 3 dB better than the worst pair-to-pair NEXT specified within the cable.

WHAT IS THE EFFECT OF ALIEN NEXT ON AN IBDN 4800LX CHANNEL? An IBDN 4800LX cabling system is designed to have additional Insertion Loss headroom and doesn’t require temperature de-rating for cable temperatures as high as 60 °C. Also the cable PSNEXT is at least 6 dB better that the Category 6 specification at frequencies up to 400 MHz. This additional headroom more than compensates for the effect of Alien NEXT.

•4

CABLING PERFORMANCE

The results for the IBDN 4800LX cabling system are presented in Table 3. For this case we will keep the same conditions as a minimally compliant Category 6 system but calculate the SNR at a much higher frequency of 250 MHz. We find that even under the most pessimistic assumptions for Alien NEXT, the SNR is still positive by 0.5 dB at 250 MHz. Note that under these very pessimistic conditions, the magnitude of Alien NEXT is almost twice as high as the PSNEXT within the cable.

Table 2 – Effect of Alien NEXT on SNR

The effect of Alien NEXT on the Signal-to-Noise Ratio is shown in Table 2. From our own experience, a realistic assumption for Alien NEXT is 6 dB worse that predicted from the equations for Category 6 bundled cables. This condition is shown in Table 2 as the realistic case. For the realistic case, the SNR is now negative 0.3 dB. For a pessimistic case, the Alien NEXT would be about 8 dB worse. This level would be approximately the same as the Category 5e bundled cable requirement. For the pessimistic case the SNR is now negative 1.0 dB.

Table 3 – Effect of Alien NEXT on SNR for an IBDN 4800 Channel

What does this mean? It means that when taking Alien NEXT into account there is a reduction in Bandwidth. However, Category 6 performance can be achieved even in the most pessimistic case by having a channel with some extra PSNEXT margin.

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Cabling Parameters and How they Affect Network Performance •4

CABLING PERFORMANCE

SIGNAL-TO-NOISE RATIO AND BIT ERROR RATE PERFORMANCE Figure 5 shows a representative Signal Power spectrum and the method of determining Signal-to-Noise ratio (SNR) for digital networks. The available Bandwidth of the channel is the frequency range where the SNR is positive. The weighted-average SNR is calculated by taking the magnitude of the Signal and the Noise as a power ratio at each frequency, adding up the power ratios and then converting it to dBs.

THE END OF THE JOURNEY We have taken you on a journey, to look at the whole issue of cabling performance and how it relates to network performance. We hope that the information presented was helpful to understand the different cabling parameters and how they all relate together to affect network performance. Like the vision we have for our life, today is only a step towards where we want to be at the end of our journey. The vision is to complete all the technical specifications for a “next generation” Category 6 cabling system that has at least twice the bandwidth of Category 5 / 5e under realistic worst case conditions. The Category 6 standard has been under development in TIA and ISO since the end of 1997. It is in the final stages of completion and is expected to be ratified this year.

Figure 5 – Weighted Average Signal-to-Noise over Available Bandwidth

The probability of errors is related as a mathematical function to the weighted-average Signal-to-Noise Ratio. This relationship is illustrated in Figure 5. Gigabit Ethernet (1000BASE-T) uses a 5-level PAM coding and requires an SNR of 18 dB to meet an error-rate objective of one bit error in 10 billion bits of information transmitted (1x10-10). Fast Ethernet (100BASE-TX) requires a SNR of approximately 15 dB.

Figure 6 – Bit Error Rate as a function of SNR and Encoding

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Category 6 cabling provides a much higher Signal-toNoise ratio than Category 5e, at least 12 dB at 100 MHz. This translates into higher data throughput (fewer bit errors) for today’s applications and more reliable operation in the presence of external noise. Category 6 also provides the Bandwidth to support future applications that are designed to take advantage of the extended Bandwidth and SNR performance.

What is Guaranteed Performance INTRODUCTION Networks are crucial to modern enterprise. Just as the strongest body would lie helpless without a nervous system, so too would a business without a network. And the structured cabling system, though it may represent only 20% of network investment, may account for up to 80% of network efficiency. Compared to the 5-year average lifespan of active equipment, the 10- to 20-year lifespan of structured cabling systems means a weak system will command company operations far into the future. Networks are complex, requiring products from many industries: structured cabling, plus switches, routers, connectors and endpoint devices. If the structured cabling system is strong, providing high performance, and is designed to handle future needs, it will be transparent; no one will notice it, as it should be. Upgrades to active equipment will go smoothly. A strong structured cabling system will obey network needs. If the structured cabling system is weak, the network will under-perform and fail to give targeted data throughput; costly re-working of the whole building cabling infrastructure may be required when introducing the next generation of active equipment. A weak structured cabling system will command overall network performance or the type of active equipment that can be installed. THE STANDARDS: A MINIMUM REQUIREMENT, NOT A TARGET With so many companies and technologies involved, IEEE developed minimum required performance levels for each network component, in order to ensure overall network performance. The minimum required performance for structured cabling has been developed by TIA (Telecommunications Industry Association). The advantages of a standards-based system for the enduser are many, including: • Not being held prisoner to any one manufacturer: with the standards accepting no proprietary solutions, the customer is free to choose components from competing manufacturers. • Guaranteed compatibility with active components: any standard-compliant system will support any standardcompliant network application. • Clear performance reporting: measurement processes and limits have been defined, which reduces confusion at the end-user level.

However, major manufacturers provide structured cabling solutions that exhibit performance well beyond standards. Beyond-standards performance represents a strong value proposition. • NORDX/CDT’s 4800LX system, for example, has a bandwidth of 300MHz, compared to the 200MHz standard for Category 6. • A standard represents a minimum required level of performance; cutting-edge technology requires performance beyond standards. • High performance systems are more forgiving than lower performance systems: any negative effects that result from installation, design or environmental factors will not compromise network performance.

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CABLING PERFORMANCE

To make such value-added propositions, cabling system manufacturers strive to propose and design high performance channels. Marketing strategies are structured around performance reporting. Moreover, the performance of today’s structured cabling systems must be compatible with tomorrow’s active equipment needs. BUT WHAT IS PERFORMANCE? The definition of performance — the execution or accomplishment of work; the efficiency with which something fulfills its purpose — is open to interpretation. • Is it the ability to perform in a laboratory? • Is it the ability to perform at any customer site? For end users, the only important ability to perform is at the installation site; the only performance that matters is guaranteed performance. One must be very careful when comparing system performance. All manufactured products have variations, and these variations induce variations in the product characteristics. For example, if one purchased ten 1-litre bottles of water and precisely measured the volume of water inside each, one bottle might contain 1.05 litres, another 1.01 litres. Statistically, 1.01 would be the minimum value, 1.05 the maximum value and, maybe, 1.04 the average value for ten bottles.

A “just-standard-compliant” system will have limitations. • Standards requirements lag behind technology advancements: standards requirements are determined mainly by consensus and therefore represent the minimum requirements the industry can or must provide.

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What is Guaranteed Performance •4

Let’s assume Manufacturer B has 1.005 as an average value, but poor process control. The following table compares the performance of A vs. B.

CABLING PERFORMANCE #1 #2 #3 #4 #5 #6 #7 #8 #9 # 10 Average Minimum Maximum

Manufacturer A Manufacturer B 1.044 1.019 1.018 1.039 1.027 0.977 1.019 1.037 1.029 0.964 1.003 0.954 1.035 1.044 1.016 1.017 1.015 0.951 1.040 1.046 1.025 1.005 1.003 0.951 1.044 1.046

Which manufacturer is better for the end-user? A or B? Manufacturer A is better. The process is more controlled, giving better results (variation between minimum and maximum of only 0.041 liter, vs. 0.095), and the minimum value from Manufacturer A (1.003) is better than the minimum value from Manufacturer B (0.951). But, depending on how the performances are reported, Manufacturer B can confuse the customer. For example, B can promote 1.005 as a typical content, or 1.046 as a possible content (this strategy is used in cabling marketing when promoting unclear ‘’typical’’ performance). This “confusion” of “performances” is found widely in structured cabling system performance reporting.

PERFORMANCE REPORTING, A NUMBERS GAME… The following table summarizes the different types of reported performances and their limitations.

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Fiber Channel Solution

Fiber-to-the-Desk (FTTD) and and Centralized Fiber

Fiber Backbone (in-building)

Typical

• A group of channels are installed, their performances measured, and the “typical” performance is reported.

• No evidence that the system described will ever be installed at a customer site. • What is “typical’’?

Worst case

• One channel is installed, and the performance of the worst pair is reported.

• No evidence that the system described will ever be installed at a customer site. • Most likely, the worst pair of the best cable ever measured will be reported.

Average

• A group of channels are installed, their performances measured, and the average performance reported.

• Systematic removal of any imperfection by averaging results.

Mathematically derived

• The performance of each component of the channel is specified, and the overall channel performance is calculated based on component performance, and a channel performance model.

• No direct link with a channel installed at a customer site. • Used when two companies make an alliance to propose a channel. Such a model allows each company to develop its own components (cables & connectivity) and to blame the other if failure is noted.

Tested up to…

• The component has been tested up to a given frequency as part of the routine quality control procedure.

• If no performance requirement is associated with the frequencies, then it has no additional value for end-users. Moreover, at high frequencies the test results are dominated by measurement noises.

Guaranteed for a complete system family

• A set of performance is guaranteed for a complete product line, such as a patch panel or IDC with patch cords.

• Simple, reliable performance reporting. The customer can be sure the system installed at his location will exhibit such performance. In the bottled water example, Manufacturer A can guarantee one liter, Manufacturer B cannot.

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What is Guaranteed Performance HOW TO ACHIEVE GUARANTEED HIGH PERFORMANCE? High performance structured cabling systems are very sensitive to the following variables:

•4

CABLING PERFORMANCE Quality of design

Fiber-to-the-Desk (FTTD) and and Centralized Fiber

Component performance

• Channel performance derives from each component’s performance: the cable and all connectivity components must be optimized. To offer the best solution, each component must exhibit high performance.

Matching components

• Component matching allows one to achieve optimum channel performance. For example, the choice of matched patch cords allows one to take full advantage of a jack’s high transmission characteristics. By using unmatched components, one obtains “just-standard-compliant” performance.

One manufacturer for all components

• To achieve a finely tuned, optimized structured cabling solution, one should choose a manufacturer that has complete control over cable and connectivity component design and production. This will ensure outstanding results…and one source for technical support.

Quality installation

• Craftsmanship is critical to Category 6 systems. Installers must be well trained and certified. Only a few companies have stringent policies for selecting and training installers.

The only reliable performance rating is guaranteed performance: end-users need to know what their onsite system performance will be, not the system performance measured in laboratories under ideal conditions. The only way an end-user can be assured of a specific level of onsite performance is to obtain an onsite performance guarantee from the manufacturer. SUMMARY This brief report highlights the importance of a built-in performance margin in one’s structured cabling system, a margin that will accommodate system variances caused by installation or environmental factors and will support tomorrow’s active equipment needs. Furthermore, it underscores the important of understanding how the performance values are reported. Typical, average or possible values under ideal conditions are not what counts — guaranteed channel performance after installation makes the difference. Channel performance takes into account all system components and identifies any weak links due to installation or design.

CHECK LIST Before comparing any performance numbers, one must ask the following questions to compare channel performance: 1. Are the performance numbers guaranteed values or nonguaranteed values? 2. Are guaranteed values clearly stated in the certification or warranty documentation? 3. What restrictions limit the guaranteed values? 4. Are all channel components optimized? Does the same company manufacture them? 5. What policies does the manufacturer have in place to ensure that system installers are properly trained and certified?

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