IBDN System Design and Applications - Belden

IBDN System Design and Applications

NOTES 

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IBDN SYSTEM DESIGN INFORMATION 

To assist designers and planners of Cabling Systems, the 

following chapter provides Design and Application 

information for IBDN Systems capable of supporting 

voice, data, LANs, imaging and video services. 

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. 

IBDN System Design Information 

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IBDN SYSTEM 

DESIGN INFORMATION 

Introduction 

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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. 

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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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. 

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 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. 

Figure 2: Entrance Facilities 


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.). 

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. 

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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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 Site Consideration 

The following considerations should be taken into account 

when selecting the location for the equipment room: 

• 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 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 m 2 

(150 ft. 2). 

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.). 

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. 

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.

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. 

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. 


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 A B C 

UTP (Data) 90 m N/A** N/A** 

(295 ft.) 

UTP (Voice) 800 m 300 m 500 m 

(2 624 ft.) (984 ft.) (1 640 ft.) 

Multimode fiber*** 

(62.5/125 µm 2 000 m 300 m 1 700 m 

or 50/125 µm) (6 560 ft.) (984 ft.) (5 576 ft.) 

Singlemode*** 3 000 m 300 m 2 700 m 

fiber (9 840 ft.) (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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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. 

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. 

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. 

Pulling tension for 22, 24 and 26 AWG copper backbone 

cables shall be respected. 

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TELECOMMUNICATIONS ROOM 

The telecommunications room houses cross-connect 

and interconnect hardware to provide circuit connection 

and administration between backbone cabling and 

horizontal cabling. 

Electronic equipment such as LAN hubs can be placed in 

the telecommunications room, but should serve only the 

area covered by the telecommunications room. 

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 m 2 

(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 Room Size 

(m2 ) (ft. 2 ) (m) (ft.) 

1 000 10 000 3 x 3.4 10 x 11 

800 8 000 3 x 2.8 10 x 9 

500 5 000 3 x 2.2 10 x 7 

Table 2:Telecommunications Room Size Recommendations

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. 

Figure 7: Horizontal Cabling 


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. 

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. 

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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 

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• 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 

Unshielded power lines 

Minimum Separation Distance 

(5 kVA) 

or electrical equipment 127 mm 305 mm 610 mm 

in proximity to open or 

non-metal pathway 

Unshielded power lines 

(5 in.) (12 in.) (24 in.) 

or electrical equipment 64 mm 152 mm 305 mm 

in proximity to a 

grounded metal 

conduit pathway 

Power lines enclosed 

in a grounded metal 

(2.5 in.) (6 in.) (12 in.) 

conduit (or equivalent — 76 mm 152 mm 

shielding) in proximity 

to a grounded metal 

conduit pathway 

(3 in.) (6 in.) 

Fluorescent lighting 305 mm (12 in.) 

Table 3: Minimum Separation Distance 

Between EMI Sources and UTP Medium

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. 

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. 


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. 

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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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 B C 

Total Channel 

Length 

Meters Meters Meters Meters 

(feet) (feet) (feet) (feet) 

5 (16) 90 (295) 5 (16) 100 (328) 

5 (16) 85 (279) 9 (30) 99 (325) 

5 (16) 80 (262) 13 (44) 98 (322) 

5 (16) 75 (246) 17 (57) 97 (319) 

5 (16) 70 (230) 22 (72) 97 (319) 

Table 4: Horizontal and Work Area Cabling Lengths

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. 

15 m (50 ft.) 

≤ 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. 

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. 


Figure 11:Work Area 

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. 

www.nordx.com 

•2 



51

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52 

• 


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 T568A T568B 

1 White-green White-orange 

2 Green-white Orange-white 

3 White-orange White-green 

4 Blue-white Blue-white 

5 White-blue White-blue 

6 Orange-white Green-white 

7 White-brown White-brown 

8 Brown-white Brown-white 

Table 5:Telecommunications Outlet Pin/Pair Designation 

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. 

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). 

www.nordx.com 

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: 

• 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: 

• Wall Mount FiberExpress System 

• Rack Mount FiberExpress System 

• Rack Mount FiberExpress Bar System 

• Frame Mount FiberExpress Manager System 

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. 

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 is a comprehensive system of quality products, 

design guidelines and installation practices backed by a 

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 responsib- 

ility 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, conse- 

quential, indirect or exemplary (punitive) damages. 

IBDN Systems Matrix 

www.nordx.com 

•3 

IBDN SYSTEMS MATRIX 

53

54 

• 

IBDN SYSTEMS 

MATRIX 

3 


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 

Systems 


GigaFlex 1200 


GigaFlex 2400 

Available 

Channel Guaranteed 

Bandwidth Data Rate 

160 MHz 

PowerSum 

250 MHz 

PowerSum 

IBDN 300 MHz 

GigaFlex 4800LX PowerSum 

IBDN Solutions 

1.2 Gb/s 

2.4 Gb/s 

4.8 Gb/s 

* ANSI/TIA/EIA-568-B.1 

** TIA/EIA Final Cat 6 – June 2002 

ISO / IEC JTC1/SC 25/WG 3 N696 – April 2001 

www.nordx.com 

IBDN Gigabit Cabling Solutions 

UTP 

Channel Std 

Compliance 

Cat. 5e * 

TIA/EIA 

IEEE Gigabit 

Cat. 6 ** 

TIA/EIA 

ISO/IEC 

IEEE Gigabit 

Beyond Cat. 6** 

TIA/EIA 

ISO/IEC 

IEEE Gigabit 

Backbone 

Cable 

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 

Cross-Connect 

Hardware 

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

IBDN GigaFlex 1213 4-pair (CMP) 

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

PS5E HD-BIX Patch Panel 

PS5E HD-110 Patch Panel 

Flex Patch Panel/EZ-MDVO PS5E Module 

Flex Patch Panel/GigaFlex PS5E Module 

110 Cross-Connect System 



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

GigaFlex PS6+ Patch Panel 



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

GigaFlex PS6+ Patch Panel 

Telecom Room Work Area 

Cross-Connect 

Patch System 

Horizontal 

Cable 

Outlets 

(Connectors - 

Faceplates & 

Adapters) 

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

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

PS5E Modular Cords 

PS5E 110 Patch Cords 

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

MediaFlex Outlets 

Interface Plates 

MDVO Faceplates 

MDVO Adapters 

European Style Faceplates 

French Style Faceplates 

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

GigaBIX Patch Cords IBDN GigaFlex 2413 4-pair (CMP) MediaFlex Outlets 

PS6 Modular Cords IBDN GigaFlex 2424 4-pair (LSOH) Interface Plates 


MDVO Adapters 



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

GigaBIX Patch Cords IBDN GigaFlex 4813 4-pair (CMP) MediaFlex Outlets 

PS6 Modular Cords IBDN GigaFlex 4824 4-pair (LSOH) 

Interface Plates 


MDVO Adapters 



Modular 

Cords 

PS5E Modular Cords 

PS6 Modular Cords 

PS6 Modular Cords


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. 

IBDN FIBEREXPRESS 

SYSTEM MATRIX 

Fiber Channel 

Solution 

Cables 

FX300 : 62.5/125 µm 

Multimode cable 

FX600 : 50/125 µm 


FX2000 : “850 nm 

Laser-Optimized 

50/125 µm” 


Singlemode cable 

Cross-Connect 

Hardware in the 

Telecommunications 

Room 

Patch cords in the 

Telecommunications 

Room and at the 

Work Area 

Patch Cords in the Telecommunications Room and at the Work Area 

Outlets at the 

Work Area 

Outlets at the Work Area 

Fiber connectivity 

Fiber Connectivity 

Fiber-to-the-Desk 

(FTTD) and and 

Centralized Fiber 

• Breakout, distribution 

or interconnect cable 

series (offered in all 

Multimode or 

Singlemode cable) 

• FiberExpress Manager 

• FiberExpress rack 

mount patch panel 

• Fiber Patch Cords: SC, SC Duplex, ST-Compatible, MT-RJ, LC, FC (available with Multimode 

FX300, FX600, FX2000 or Singlemode cable) 

• MDVO Multimedia 

Outlet Box 

• Multi-User Outlet Box 

• MDVOFlex Outlet with 

MDVOFlex Mutlimedia 

Inserts 

• Interface Outlet with 

MDVOFlex Mutlimedia 

Inserts 

FIBER CHANNEL TOPOLOGIES 

Fiber Backbone 

(in-building) 

• Breakout or distribution 

cable series 

(offered in all 

Multimode or 





• FiberExpress wall 


• 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 


(campus environment) 

• Breakout or distribution 

cable series 

indoor, outdoor, 

indoor/outdoor or 

armored (offered in all 

Multimode or 





• FiberExpress wall 


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. 

FiberExpress Preterminated 

Solutions* 

• FiberExpress Ribbons 

cable series (offered in 

all Multimode or 


• FiberExpress Bar 


• FiberExpress Bar 

www.nordx.com 

•3 

IBDN SYSTEMS 

MATRIX 

55

NOTES 

Notes 

• 

•

Whether you are a telecommunications consultant, sys- 

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

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 regard- 

ing what are the important issues affecting cabling sys- 

tem 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 under- 

standing 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. 

Cabling Performance 

www.nordx.com 

•4 

CABLING PERFORMANCE 

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58 

• 

4 


Cabling Parameters and 

How they Affect Network 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. 

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). 

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. 

www.nordx.com 

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. 

Figure 1 - Effect of Component Impedance Mismatch 

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,

the Impedance of connecting hardware varies depending 

on design and the type of compensation circuitry that is 

used. 

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. 

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. 

Figure 2 – Channel Figure Insertion 2 Loss and ILD 

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 



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. 

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. 

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 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. 

www.nordx.com 

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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. 

www.nordx.com 

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.

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. 

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. 

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. 



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. 

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

www.nordx.com 

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• 



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. 

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 

www.nordx.com 

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. 

Category 6 cabling provides a much higher Signal-to- 

Noise 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.

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. 

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. 

What is Guaranteed Performance 

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. 

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. 

www.nordx.com 

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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. 

Manufacturer A Manufacturer B 

# 1 1.044 1.019 

# 2 1.018 1.039 

# 3 1.027 0.977 

# 4 1.019 1.037 

# 5 1.029 0.964 

# 6 1.003 0.954 

# 7 1.035 1.044 

# 8 1.016 1.017 

# 9 1.015 0.951 

# 10 1.040 1.046 

Average 1.025 1.005 

Minimum 1.003 0.951 

Maximum 1.044 1.046 

www.nordx.com 

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. 

Fiber Channel 

Solution 

Typical 

Worst case 

Average 

Mathematically 

derived 

Tested up to… 

Guaranteed for 

a complete 

system family 

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

Fiber 

• A group of channels are installed, their 

performances measured, and the “typical” 

performance is reported. 

• One channel is installed, and the performance of 

the worst pair is reported. 

• A group of channels are installed, their performances 

measured, and the average performance 

reported. 

• 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. 

• The component has been tested up to a given 

frequency as part of the routine quality control 

procedure. 

• A set of performance is guaranteed for a 

complete product line, such as a patch panel or 

IDC with patch cords. 


(in-building) 

• No evidence that the system described will ever 

be installed at a customer site. 

• What is “typical’’? 

• 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. 

• Systematic removal of any imperfection by 

averaging results. 

• 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. 

• 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. 

• 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.


HOW TO ACHIEVE GUARANTEED HIGH PERFORMANCE? 

High performance structured cabling systems are very sensitive to the following variables: 

Quality of design 

Component performance 

Matching components 

One manufacturer for all 

components 

Quality installation 

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

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. 

• 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. 

• 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. 

• 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. 

• 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. 

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? 

www.nordx.com 

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NOTES 

Notes 

• 

•

IBDN System Design and Applications - Belden

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