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What is structured cabling?
The importance of structured cabling.
A structured cabling system is as important to the success of your organization
as the people are who work in it.
A well-planned structured cabling system facilitates the continuous flow of
information, enables the sharing of resources, promotes smooth operations,
accommodates ever-changing technology, offers plenty of room for growth,
and evolves with your organization. Plus, it will be around far longer than
your current PC, server, and network switches.
In essence, a structured cabling system is the lifeblood
of your organization. If done right, it will serve you well
for years. If not, your organization’s growth and bottom
line can suffer.
The importance of structured cabling has increased
right alongside the growth of LANs, MANs, and WANs.
It started with individuals working on standalone PCs.
It didn’t take long to connect those PCs into workgroups
and then to connect those workgroups to a server.
One server became multiple servers. And the rest is
history. Today’s networks are complex systems running
on technologies that no one could have imagined just
15 years ago.
This guide will provide an overview of the standards
and practices that govern structured cabling systems.
For expert advice on your new or upgraded structured
cabling system, and for complete services ranging
from design and products through installation
and maintenance, call Black Box at 724-746-5500
or go to blackbox.com.
Astructured cabling system is the wiring network that carries all your
data,voice,multimedia,security,VoIP,PoE,and even wireless connections
throughout your building or campus.It includes everything from the data
center to the desktop,including cabling,connecting hardware,equipment,
telecommunications rooms,cable pathways,work areas,and even the jacks
on the wallplate in your office.

Introduction
Planning your structured
cabling system ...................................2–3
Networking
Network applications...............................4
Network topologies ................................5
Standards
Organizations ...........................................6
Key standards............................................7
Cabling
Considerations ..........................................8
Choosing cable..........................................8
Copper cable .............................................9
Copper cable standards ...................10–11
10-GbE cable ...........................................11
Fiber cable.........................................12–13
The Structured Cabling System
Introduction......................................14–15
Horizontal cabling............................16–18
Backbone cabling.............................19–20
Work area................................................21
Telecommunications room ....................22
Equipment room ....................................23
Entrance facility......................................23
Pathways ...........................................24–25
Installation and Testing
Cable installation practices....................26
Cable testing.....................................27–29
Other Standards
Structured cabling administration ........30
Industrial environments.........................31
Data center infrastructure...............32–33
Power over Ethernet ..............................34
Wireless networking ..............................35
Products...................................................36–40
Glossary...................................................41–43
Index ..............................................................44
Designer: Darlene Davis
Writers: Roberta Szyper
Caren Bachmann
Jonathan Decker
Editor: Julie Daubner
Technical Consultant: Andy Schmeltzer
© Copyright 2007. Black Box Corporation.
All rights reserved, Printed in U.S.A.
Table of Contents
1

2 Black Box Guide to Structured Cabling
Section Name
Section Name
Introduction
Planning your structured cabling
The most important design considerations.
If you do nothing else, weigh these considerations carefully.
Applications. Your system should support data, voice,
video, and multimedia applications now and well into
the future. You should anticipate applications
involving VoIP, PoE, wireless, and security.
Life cycle. Plan on a life span of
15–20 years, with 10 years as the
minimum. Your cabling system
should have the longest life cycle
of any component in your network.
Compare that to a network switch,
which has an average life span of five years.
Compatibility. Your system should be based
on open standards and be able to support multiple
applications regardless of the vendor. Modular, open-
standard systems enable easy changes and easy expansion
without changing the cabling and equipment.
Bandwidth. The demand for it just keeps growing. The more
the better. Enough said.
Growth. Anticipate how many users you’ll need to support
10, 15, or even 20 years down the road. See Bandwidth above.
MACs (Moves, adds, and changes). Your network should
facilitate and accommodate frequent changes.
Astructured cabling system that’s smartly designed takes careful planning. Systems are
more complex now than ever, and will get even more so as speed and bandwidth demands
increase. The system you plan today will be supporting new and different applications for many
years. Take your time, review everything, and get ready for the future. For guaranteed-for-life
products, expert advice, and complete installation services, call Black Box.

Other important design considerations.
Usage. When planning a network, consider peak loads of all
applications, usage patterns, type of traffic, and outlet density.
Future technology. In this business, change happens fast.
See Bandwidth on the previous page.
Location of users. Where are users and how far are they from
the network switches? Will a collapsed backbone work better?
Centralized cabling? Zone cabling?
Power over Ethernet. Consider where you may need to run
power over your data lines.
Wireless access points. Plan on complete coverage.
VoIP. Voice over Internet Protocol is fast becoming the network
type of choice.
Security. Plan on current and emerging data, network, and
physical security systems, including PoE and wireless applications.
Regulations. NEC. ANSI/TIA/EIA. State and local building codes.
They exist for a reason so be sure to abide by them.
Space. Consider available space for data centers, equipment,
telecommunications rooms, and cable runs. Factor in plenum runs,
additional air ducts, sprinkler systems, suspended ceilings, etc.
Physical conditions. Consider any unusual physical constraints, such
as power lines, EMI influences, seismic activity, industrial activity, even
being below water level. For a listing of the Ingress Protection (IP)
ratings, see page 31.
Media. The type of cable you choose may depend on the
applications, architecture, environment, and more.
Redundancy. Consider whether you need duplicate pathways
to run redundant backbones for mission-critical applications.
Site survey. A comprehensive site survey should be done to
identify users’ equipment, locations, and regulations that require
attention.
Maintenance. Who is going to do it, how often, and at what
cost. Consider whether you’re going to use in-house technicians
or a contracted service.
Warranties. What do they cover? Most should cover the
cabling components and the application the system was
designed to support.
Documentation. Don’t forget proper documentation, diagrams,
labeling, color coding, and other administrative duties. Doing it right
the first time will make your life a whole lot easier in the future.
Last, but not least.
Total cost of ownership. This can be tricky. The lowest initial
installation cost is not always the least expensive. You also have
to factor in the cost of upgrades and recurring costs over the
lifetime of the system. The greatest expenses after your original
investment will be MACs and equipment upgrades. Plan on
replacing your electronic equipment three to four times over the
life of the cabling system. When all totaled, these ongoing costs
can actually equal or exceed the cost of your original investment.
You also have to consider the quality of the installation. The
lowest bid may not necessarily be the best. A well-planned and
documented installation will more than pay for itself by lowering
long-term maintenance, eliminating problems from poor
workmanship, reducing downtime, and most importantly,
giving you peace of mind.
3
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Introduction
system
Class F/CAT7 (draft):
600 MHz
CAT6a: 500 MHz
CAT6: 250 MHz
CAT5e: 100 MHz
Single-mode fiber
(campus backbone)
50-µm multimode fiber
(recommended backbone)
62.5-µm multimode fiber
(traditional backbone)
Structured Cabling System with Mixed Media

Ethernet Standards
Network Standard IEEE Cable Speed Distance
Ethernet 10BASE5, 2 802.3 Coaxial 10 Mbps 500 m/185 m
10BASE-T 802.3i CAT3 10 Mbps 100 m
10BASE-F, -FB, FL, FP 802.3 Fiber 10 Mbps 2000 m/500 m
Fast Ethernet 100BASE-TX, T4 802.3u CAT5 100 Mbps 100 m
100BASE-FX 802.3u MM Fiber 100 Mbps 400 m half-duplex,
2 km full-duplex
Gigabit Ethernet 1000BASE-T 802.3ab CAT5e/CAT6 1000 Mbps 100 m
1000BASE-LX 802.3z MM, SM Fiber 1000 Mbps 550 m/5000 m
1000BASE-SX 802.3z MM Fiber 1000 Mbps 550 m
10-Gigabit Ethernet 10GBASE-SR, -LR, LX
-ER, -SW, -LW, -EW 802.3ae MM, SM Fiber 10 Gbps 65 m to 40 km
10GBASE-CX4 802.3ak 100-Ω Twinax 4 x 2.5 Gbps 15 m
10GBASE-T 802.3an UTP 10 Gbps 100 m
Most likely, the network you use now and in the future will be
some form of Ethernet. It’s the most common network type, and it’s
the de facto standard in networking.
The original Ethernet networks (10BASE5 and 10BASE2) ran over
coaxial cable. An upgrade, 10BASE-T, the first vendor-independent
implementation of Ethernet, operated over unshielded twisted-pair
cable at a then speedy 10 Mbps. As technology progressed, so did
Ethernet—it went to 100BASE-TX, which runs at 100 Mbps and
specifies a minimum of CAT5 cable, although CAT5e is more common.
Section Name
Section Name
Networking
Gigabit Ethernet (1 Gbps) was developed to handle backbone
and server traffic, and is now also deployed to the desktop. When
Gigabit Ethernet first appeared, fiber was crucial to running it
effectively. Later the IEEE 802.3ab standard approved Gigabit
Ethernet over Category 5 cable, although CAT5e or higher is the
norm. Today, it is one of the most commonly installed networks.
10-Gigabit Ethernet (10-GbE) brings the familiarity and cost-
effectiveness of Ethernet to high-performance networks with
a speed ten times that of Gigabit Ethernet and a frequency of
500 MHz. It supports high-bandwidth applications, such as imaging
and storage. 10-Gigabit Ethernet enables the construction of MANs
and WANs that connect geographically dispersed LANs. Today, the
most common application for 10-Gigabit Ethernet is as a backbone
connecting high-speed LANs, server farms, and campuses.
10-GbE over fiber was ratified in 2002. An IEEE amendment in
2006, 802.3an, approved 10-GbE over twisted pair. The TIA/EIA-568-
B.2.10 draft specifies transmission performance for Augmented
Category 6 cable. The TSB-155 addresses existing Category 6 cabling
for 10-GbE. It’s emerging as the standard to wire for now. For more
information on 10-GbE, see page 11.
Think fast.
When planning a network, think fast. Network technologies
considered cutting edge only a few years ago are now becoming
viable options for network upgrades. The shift is to Gigabit
Ethernet, 10-GbE, SANs (storage area networks), and even 40+Gbps
connections for enterprise and data center backbones.
Other networks.
Other networks exist, but
they’re uncommon. Before
the establishment of open-
architecture, standards-based
networks like Ethernet,
proprietary networks, such
as IBM®
Token Ring, were
the norm.
Network applications (or the evolution of Ethernet)
TECH TIP
A short history of Ethernet — Since 1985, when 10-Mbps
Ethernet was first standardized, demand for bandwidth and speed
has grown steadily alongside increasingly high-performance
applications—thus the standardization of 100-Mbps Fast Ethernet
in 1995; Gigabit Ethernet in 1998, and in the ratification of
10-Gigabit Ethernet in June 2002. Each step forward represents
a tenfold increase in performance.
10-Gigabit Ethernet is a logical extension
of previous Ethernet networks, which are the
predominant technology for high-performance
LANs.

Ring Topology
Bus.
A bus topology consists
of one continuous cable,
commonly called the backbone
cable. Devices are connected
along that cable, and informa-
tion travels in a linear fashion
along the entire length of the
bus. Devices can be removed
from the bus without disrupting
the entire network. The original
Ethernet topology was a bus.
There are three basic network topologies: star, ring, and bus.
Star.
The star network features individual point-to-point cable runs
radiating from a central equipment room, which can house a PBX
in voice networks or switches in data networks. The advantage of
a star network is that you can connect and disconnect equipment
without disrupting the rest of the network. The star network
facilitates smooth moves, adds, and changes. 10BASE-T and
later versions of Ethernet use a star topology.
The TIA/EIA makes a few design recommendations for
star topologies.
• There shall be no more than two hierarchical levels
of backbone cross-connects.
• Bridged taps and splices shall not be installed.
• Proximity to sources of EMI shall be taken into account.
• Grounding should meet J-STD-607-A requirements.
NOTE: The TIA/EIA has two basic categories of recommendations:
mandatory and advisory. Mandatory criteria are designated by the
word “shall.“ So if you see the word shall, pay attention. Advisory
criteria are recommended, but not absolutely necessary.
Ring.
A ring topology links a series of devices in a continuous loop.
A ring is a simple network, but it has a few disadvantages. All the
signals are passed from one device to the next until they reach the
intended station.
5
Networking
Bus Topology
Star Topology
Network topologies

Section Name
Section Name
Standards
The importance of standards
The importance of standards in today’s structured cabling
systems can’t be underestimated.
A standards-based system provides a generic base for building
a communications infrastructure without compatibility worries.
Standards establish
technical criteria
and ensure uniform
performance among
network systems and
components. They enable
you to build modular
networks that can easily
accommodate new technologies,
equipment, and users.
Before 1985, there were no
structured cabling standards. Phone
companies used their own cabling.
Businesses generally used a vendor’s
proprietary system. Eventually, the
Computer Communications Industry
Association (CICIA)
approached the Electronics
Industries Alliance, formerly
Association, (EIA) about
developing cabling standards,
which they did. Discussions
centered around developing
standards for voice,
data, commercial, and
residential cabling
systems. (The TIA
was formed
in April 1988
after a merger
of the United States
Telecommunications Suppliers Association
and the Information and Telecommunications Technologies
group of the EIA. Thus the TIA/EIA.)
In 1991, the TIA/EIA published its Commercial Building
Telecommunications Wiring Standard, TIA/EIA-568. It was
the first standard to define a generic telecommunications system
that would support a multiproduct, multivendor environment.
It enabled wiring systems to be planned and installed without
definite plans for telecommunications equipment installed later.
The standards committees meet and review standards every
five years, and the issuance of TSB (Technical Service Bulletins)
is on-going. The TIA/EIA has issued a number of standards covering
everything from types of cabling, cabling installation, administration,
and more. This guide covers the most relevant standards to
commercial buildings.
Standards organizations.
Today, there are a number of organizations developing
standards related to cabling and communications.
ANSI (American National Standards Institute). This group
coordinates and adopts national standards in the U.S.
EIA (Electronics Industries Alliance). Best known for developing
cabling standards with the TIA, this trade organization is accredited
by ANSI to help develop standards on electronics components,
telecommunications, Internet security, and more.
TIA (Telecommunications Industry Association). Best known
for developing cabling standards with the EIA, the TIA is the
leading trade association for the information, communications,
and entertainment technology industry. The TIA provides standards
development and represents the communications sector of the
Electronics Industries Alliance (EIA).
ISO (International Organization for Standardization). This group
is the world’s largest developer of standards and includes standards
groups from member nations around the world.
IEC (International Electrotechnical Commission). This international
standards organization prepares and publishes international standards
for all electrical, electronic, and related technologies.
IEEE (Institute of Electrical and Electronics Engineers, Inc.).
This international organization is a leading developer of industrial
standards in a broad range of disciplines, including electric
power, information technology, information assurance,
and telecommunications. This group is known for its 802.3
committee, which sets the standards for Ethernet.
BICSI (Building Industry Consulting Service International, Inc.).
This association supports the information transport systems (ITS)
industry with information, education, and knowledge assessment.
CSA (Canadian Standards Association). Electrical and electronic
goods in Canada must be CSA approved.

7
Standards
Where to buy standards
ANSI 212-642-4980
www.ansi.org
TIA/EIA Global Engineering Documents
877-854-7179 (U.S. and Canada)
www.ihs.com
ISO/IEC Available from Global Engineering and ANSI
in the U.S. and Canada
Global Engineering Documents
877-854-7179 (U.S. and Canada)
www.ihs.com
ANSI
www.ansi.org (U.S.)
ISO Switzerland: +41 22 34 12 40
IEEE 800-701-4333 (U.S. and Canada)
732-981-0060 (Worldwide)
www.ieee.org
Key standards.
ANSI/TIA/EIA
The Commercial Building Telecommunications Cabling
Standard is covered in ANSI/TIA/EIA-568-B.1, -B.2, and -B.3.
ANSI/TIA/EIA-568-B.1: Part 1: General Requirements. This
standard covers the general requirements for planning, installing,
and verifying structured cabling systems in commercial buildings.
It also establishes performance parameters for cable channels and
permanent link. One of the major changes in this document from
the earlier version is that it recognizes CAT5e or higher cabling
for the second data outlet.
ANSI/TIA/EIA-568-B.2: Part 2: Balanced Twisted-Pair Cabling
Components. This standard discusses balanced twisted-pair
cabling components and transmission requirements.
ANSI/TIA/EIA-568-B.2-1: Part 2, Addendum 1: 4-Pair, 100-Ohm
Category 6 Transmission Performance. This standard specifies
components and transmission requirements.
ANSI/TIA/EIA-568-B.2-10 (Draft): Augmented Category 6
Transmission Performance.
TSB-155: Characterizing Existing Category 6 Cabling to
Support 10-Gigabit Ethernet.
ANSI/TIA/EIA-568-B.3: Optical Fiber Cabling Components
Standard.
ANSI/TIA/EIA-568-B.3-1: Additional Transmission Performance
Specifications for 50/125 Optical Fiber Cabling Systems.
ANSI/TIA/EIA-569-B: Commercial Building Standard
for Pathways and Spaces.
ANSI/TIA/EIA-570-A: Residential Telecommunications
Cabling Standard.
ANSI/TIA/EIA-606-A: Administration Standard for
Telecommunications Infrastructure of Commercial Buildings.
ANSI/TIA-607: Commercial Building Grounding and Bonding
Requirements for Telecommunications.
ANSI/TIA/EIA-758: Customer Owned Outside Plant.
ANSI/TIA/EIA-862: Building Automation Systems Standard
for Commercial Buildings.
ANSI/TIA/EIA-942: Telecommunications Infrastructure
Standard for Data Centers
TSB-1005: Telecommunications Infrastructure Standard for
Industrial Premises
TSB-162: Telecommunications Cabling Guidelines for Wireless
Access Points.
ISO
ISO 11801:2002: Information Technology—Generic Cabling
for Customer Premises.
ISO/IEC 11801, 2nd Ed.: Includes Class D, E, and F Cabling.
ISO/IEC 11801, 2nd Ed. Amendment 1: Covers Class EA and FA.*
ISO 11801 Class Ea, Edition 2.1: 10-Gigabit over Copper.
ISO/IEC TR 24704: Information Technology—Customer
Premises Cabling for Wireless Access Points.
*NOTE: Class EA and FA are expected to be approved in Fall 2007.
IEEE
IEEE 802.3af: Power over Ethernet. (PoE).
IEEE 802.3at (draft): Power over Ethernet Plus (PoE Plus).
IEEE 802.11: Wireless Networking.
IEEE 802.3an: 10GBASE-T 10 Gbps (1250 Mbps) Ethernet
over Unshielded Twisted Pair (UTP).
Other Standards and Regulations
National Fire Protection Association: National Electrical Code
(NEC)
Occupational Safety and Health Act of 1970
State and Local Building, Electrical, and Safety Codes
and Ordinances

Section Name
Section Name
Cabling
The importance of cable
Cabling is one of the most important components of your network and is the most
long-lived with an expected life span of 15–20 years. You’ll most likely replace your
network equipment three to four times over the life of the cabling system. Plan on
cabling to be about 15% of your total network cost. And don’t skimp on the cable
or the installation. An investment in a high-quality cabling system is easily justified
in reduced downtime, reduced maintenance, and better network performance.
So think long-term and buy the best cable and installation services.
Cabling considerations.
Network application. The type of network you
plan to run will influence the cable you choose.
Upgrades. Anticipate changes and upgrades
in equipment and applications.
Life span. Expect 10 years minimum and 20 years
maximum.
Distance. Review the maximum distance between
your network switches and the farthest desktop.
Cable routing. Consider bend radius and available
space for running cables in the floor and ceiling.
Fire risk. Abide by all regulations.
Existing cable. Is there existing or abandoned
cable that needs to be removed?
EMI (electromagnetic interference). Don’t forget
to check for it.
Environment. Any physical limitations that could
affect your cable choice?
Choosing cable.
When planning your cabling infrastructure, you
have two basic choices: copper or fiber. Both offer
superior data transmission. The decision on which
one to use depends on your current network, your
future networking needs, and your applications,
including bandwidth, distances, environment, cost,
and more.
Traditionally, copper was used in lower-speed,
short-distance networks, and fiber was used in
higher-speed, long-distance networks. But with the
advent of copper cable running at 10-Gigabit rates,
this maxim no longer holds true. You may even find
a mixed network with a fiber backbone and copper
horizontal cable to be an optimum solution.

9
Cabling
Copper cable
Some of the most obvious advantages copper
offers is that it’s less expensive than fiber cable and
much easier to terminate in the field. Because copper
is the most commonly installed cable, there is a vast
selection of connecting hardware and networking
devices, which are also less expensive than fiber
equipment.
Unshielded twisted pair (UTP).
UTP. This is the most widely used cable. Known as
balanced twisted pair, UTP consists of twisted pairs
(usually four) in a PVC or plenum jacket. When
installing UTP cable, make sure you use trained
technicians. Field terminations, bend radius, pulling
tension, and cinching can all loosen pair twists and
degrade performance. Also take note of any sources
of EMI. Choose UTP for electrically quiet environments.
Shielded twisted pair (STP, F/UTP,
S/FTP, ScTP, S/STP).
Use shielded cable to extend distances and to
minimize EMI. Sources of EMI, commonly referred to
as noise, include elevator motors, fluorescent lights,
generators, air conditioners, and printers, etc. In
10-GbE, shielded cable can also reduce ANEXT.
Shielded cable can be less balanced than UTP
cable because of the shield. The metal sheaths in
the cable need to be grounded to cancel the effect
of EMI on the conductors. Shielded cable is also more
expensive, less flexible, and can be more difficult to
install than UTP cable. Most shielded cable is thicker
than UTP, so it fills conduits quicker. Keep that in
mind as you plan your cable pathways.
STP. This is twisted pair cabling with a shield. There
are two common shields: foil sheaths and copper
braids. Foil gives a 100% shield while a copper braid
provides 85% to 95% coverage because of the holes
in the braid. But, a braided shield offers better
overall protection because it’s denser than foil and
absorbs more EMI. A braided shield also performs
better at lower frequencies. Foil, being thinner,
rejects less interference, but provides better protection
over a wider range of frequencies. For these reasons,
combination foil and braid shields are sometimes
used for the best protection. Shields can surround all
the twisted pairs and/or the individual twisted pairs.
Unshielded
twisted-pair cable (UTP)
Foiled/unshielded
twisted-pair cable (F/UTP)
Stranded conductor
Shielded/foiled
twisted-pair cable (S/FTP)
Solid conductor
Foiled/Unshielded Twisted Pair (F/UTP). Foil is the
most basic cable shield. Cables with an overall foil
shield surrounding all the pairs are called F/UTP.
These may also be called FTP cables.
Shielded Foiled Twisted Pair (S/FTP). This cable
features individual foil-shielded pairs and an outer
shield, which can be braided or foil. It offers the best
protection from external noise and ANEXT. This cable
was traditionally called Screened Twisted Pair (ScTP).
You may also see it listed as S/STP.
Solid vs. stranded conductors.
Copper cable conductors can be solid or stranded,
whether the cable is shielded or unshielded.
Solid-conductor. This cable is designed for
both backbone and horizontal cable runs. Use it for
runs between equipment rooms or from the tele-
communications room to the wallplate. Solid cable
shouldn’t be bent, flexed, or twisted. Its attenuation
is lower than that of stranded-conductor cable.
Stranded-conductor. This cable is used primarily
as a patch cable between the outlet and desktop and
between patching equipment. Stranded-conductor
cable is more flexible than solid-core cable. However,
attenuation is higher, so the total length of a
stranded cable in your channel should be kept to
10 meters or less to reduce signal degradation.
PVC vs. plenum.
PVC cable features an outer polyvinyl chloride
jacket that gives off toxic fumes when it burns. It’s
most commonly used between the wallplate and
workstation. It can be used for horizontal and vertical
runs, but only if the building features a contained
ventilation system.
Plenum cable has a special coating, such as Teflon®
FEP, which doesn’t emit toxic fumes when it burns.
A plenum is a space within the building designed for
the movement of environmental air. In most office
buildings, the space above the ceiling is used for the
HVAC air return. If cable goes through that space,
it must be “plenum-rated.” LS0H (Low Smoke, Zero
Halogen) is a type of plenum cable with a thermo-
plastic compound that reduces the amount of toxic
and corrosive gases emitted during combustion.
TECH TIP
AWG — American
Wire Gauge (AWG) is
a classification system
for the diameter of the
conducting wire. The
more a wire is drawn or
sized, the smaller the
diameter. For example, a
24-gauge wire is smaller
than an 18-gauge wire.
Foil
Foil Braid

Section Name
Section Name
Cabling
Balanced Twisted-Pair Cable Specifications
CAT5 CAT5e CAT6 CAT6a CAT7
Frequency 100 MHz 100 MHz 250 MHz 500 MHz 600 MHz
Attenuation (min. at 100 MHz) 22.0 dB 22.0 dB 19.8 dB — 20.8 dB
Characteristic Impedance 100 ohms ± 15% 100 ohms ± 15% 100 ohms ± 15% — 100 ohms ± 15%
NEXT (min. at 100 MHz) 32.3 dB 35.3 dB 44.3 dB 27.9 dB 62.1 dB
PS-NEXT (min. at 100 MHz) — 32.3 dB 42.3 dB — 59.1 dB
EL-FEXT (min. at 100 MHz) — 23.8 dB 27.8 dB 9.3 dB (not yet specified)
PS-ELFEXT (min. at 100 MHz) — 20.8 dB 24.8 dB — (not yet specified)
PS-ANEXT (min. at 500 MHz) — — — 49.5 dB —
PS-AELFEXT (min. at 500 MHz) 16.0 dB 20.1 dB 20.1 dB 23.0 dB 14.1 dB
Return Loss (min. at 100 MHz) 16.0 dB 20.1 dB 20.1 dB 8.0 dB 14.1 dB
Delay Skew (max. per 100 m) — 45 ns 45 ns — 20 ns
Networks Supported 100BASE-TX 1000BASE-T 1000BASE-T 10GBASE-T (not yet specified)
As the need for increased bandwidth grows and applications
continually get more complex, so does copper twisted-pair cable.
Below are brief explanations of specifications for twisted-pair
cabling and the applications for which each is best suited.
TIA/EIA-568B specifies several “categories” for both the
components and the cable. The ISO/IEC specifies “categories”
for the components and “classes” for the cabling.
Cable categories.
Category 3 (CAT3) cable is rated for networks operating up to
16 Mbps. It is suitable for voice transmissions (not VoIP). ISO/IEC
refers to the end-to-end channel as Class C.
Category 4 cable is rated for transmission of 16 Mbps up to
100 meters. It is considered obsolete.
Category 5 (CAT5) cable was common for 100-Mbps LANs.
It was ratified in 1991 and is now considered obsolete.
Enhanced Category 5 (CAT5e/Class D) cable, ratified in 1999,
was designed to enable twisted-pair cabling to support full-duplex,
100-MHz applications such as 100BASE-TX and 1000BASE-T. CAT5e
introduces stricter performance parameters such as Power-Sum
Near-End Crosstalk (PS-NEXT), Equal-Level Far-End Crosstalk
(EL-FEXT), and Power-Sum Equal-Level Far-End Crosstalk (PS-ELFEXT).
It also introduces channel and component testing.
Category 6 (CAT6/Class E) cable easily handles Gigabit Ethernet
(1000BASE-T) applications. It’s a 100-ohm cable with a frequency
of 250 MHz. CAT6 has far more stringent performance parameters
than CAT5e, and is characterized by channel, link, and component
testing. In addition, CAT6 components must be backwards-
compatible with lower-level components. It’s important to note with
CAT6, as with all categories, that all the components in a channel
must be of the same level. If not, the channel will perform at the
lowest level.
The TIA TSB-155: Characterizing Existing Category 6 Cabling
to Support 10-Gb Ethernet, ISO/IEC 24750, and IEEE 802.3an all
address 10GBASE-T over UTP cabling. They also address installation
practices to mitigate Alien Crosstalk (ANEXT) though it is not a
specified CAT6 measurement. CAT6 is also recommended for mid-
span PoE applications. At the time of this publication (mid 2007),
CAT6 cabling is the system of choice for new installations because
of the increased headroom.
Augmented Category 6 (CAT6a/Class EA), a relatively new
standard, is designed to meet or exceed the requirements of
10-Gigabit Ethernet over copper at 100 meters. It extends the
frequency range of CAT6 from 250 MHz to 500 MHz. Like CAT6,
it includes an integrated set of channel, permanent link, and
component requirements. It introduces an Alien Crosstalk
(ANEXT) measurement for closely bundled “six around one” cable
configurations. (For information on ANEXT, see pages 28–29.) Both
UTP and F/UTP cables can be used in CAT6a deployments. The F/UTP
cable, though, virtually eliminates the problem of ANEXT.
Copper cable standards
NOTE: The ISO currently has Class FA (Category 7a) requirements under development. They are based on Class F requirements and the
Category 7 non-RJ style plug. They specify a bandwidth of 600 to 1000 MHz.

11
Cabling
Category 7/Class F is only an ISO/IEC 11801:2002 standard
and is not in a draft stage by the TIA. It’s designed to meet or
exceed the requirements of 10-Gigabit Ethernet. The standard
specifies a frequency of 1–600 MHz over 100 meters of fully
shielded twisted-pair cabling.
Category 7/Class F cable consists of four individually shielded
pairs inside an overall shield. It’s called Shielded/Foiled Twisted Pair
(S/FTP) or Foiled/Foiled Twisted Pair (F/FTP). With both, each twisted
pair is enclosed in foil. In S/FTP cable, the four pairs are encased
in an overall metal braid. In F/FTP, the four pairs are encased
in an overall foil shield.
The fully shielded cable virtually eliminates crosstalk between
the pairs. In addition, the cables are noise resistant, making the
Category 7/Class F system ideal for high EMI areas. It’s well suited
for applications where fiber optic cable would typically be used—
but costs less.
Category 7/Class F cable can be terminated with two interface
designs as specified in IEC 6063-7-7 and IEC 61076-3-104. One is an
RJ-45 compatible GG-45 connector. The other is the more common
TERA®
connector launched in 1999.
Category 7a/Class FA is a pending ISO class based on the use
of S/FTP cable to 1000 MHz.
10-GbE and twisted-pair cable.
The cabling industry is developing two different standards that
can be used in 10-GbE applications. One is for use with Category 6
(CAT6) cable, and one is for Augmented Category 6 (CAT6a). These
standards specify requirements for each component in the channel,
such as cable and connecting hardware, as well as for the permanent
link, and the channel.
10-GbE using CAT6. The first set of standards define cabling
performance when using Category 6/Class E cabling for 10-GbE
applications. The TIA/EIA version is the Technical Systems Bulletin
155 (TSB 155). ISO/IEC TR 24750 is a technical report that details
measuring existing Class E systems.
No matter what the cable length is, CAT6 cable must meet 10-GbE
electrical and ANEXT specifications up to 500 MHz. However, the
CAT6 standard now specifies measurements only to 250 MHz, and it
does not have an ANEXT requirement. There is no guarantee CAT6
can support a 10-GbE system. But the TSB provides guidelines
for ways to help mitigate ANEXT. One way to lessen or eliminate
ANEXT altogether is to use shielded cable and equipment, such
as F/UTP cable. Another way is to follow mitigating installation
techniques, such as using non-adjacent patch panels, separating
equipment cords, unbundling horizontal cabling, avoiding areas
of high EMI, etc.
10-GbE using CAT6a. The second set of standards will define
Augmented Category 6 (CAT6a) and Augmented Class E (Class EA)
cabling. The newer, augmented cabling systems are designed
to support 10-GbE over a 100-meter horizontal UTP channel.
The TIA/EIA version is in draft as of mid 2007 and will be
published as ANSI/TIA/EIA-568B.2-AD10. It recognizes both UTP
and STP CAT6a systems. It extends CAT6 electrical parameters such
as NEXT, FEXT, return loss, insertion loss, and more to 500 MHz.
It also specifies near- and far-end Alien Crosstalk (ANEXT, AFEXT)
to 500 MHz. It also goes beyond IEEE 802.3an by establishing
the electrical requirements for the permanent link and cabling
components. The ISO Class EA standard will be published
in a new edition of the 11801 standard.
Comparison of Categories and Classes
TIA TIA ISO ISO
Frequency (Components) (Cabling) (Components) (Cabling)
1-100 MHz CAT5e CAT5e CAT5e Class D
1-250 MHz CAT6 CAT6 CAT6 Class E
1-500 MHz CAT6a CAT6a CAT6a Class EA
1-600 MHz n/s n/s CAT7 Class F
1-1000 MHz n/s n/s CAT7A Class 7A
10-GbE Cabling
Link Segment
Cable Standard Distances
CAT6/Class E
Unshielded TSB-155, ISO/IEC TR-24750 55 (37*) m to 100 m
Shielded TSB-155, ISO/IEC TR-24750 55 (37*) m to 100 m
CAT6a/Class EA TIA/EIA-568-B.21-AD10 100 m
Unshielded ISO/IEC 11801 2.1
Class F ISO/IEC TR-24750 100 m
Shielded
NOTE: For S/FTP and F/UTP cable, see blackbox.com.
* TSB-155 allows 37 meters in CAT6 installations without mitigation.

Section Name
Section Name
Cabling
Fiber cable
Fiber optic technology uses light as an information
carrier. The cable consists of a core, a single continuous
strand of glass or plastic that’s measured in microns
(µ) by the size of its outer diameter. This is the
pathway for light rays carrying data signals.
Fiber is the preferred cable for applications
that require high bandwidth, long distances, and
immunity to electrical interference. It’s the most
commonly installed backbone cable as well.
The advantages of fiber.
Greater bandwidth. Because fiber provides far
greater bandwidth than copper and has proven
performance at rates up to 10 Gbps, it gives network
designers future-proofing capabilities. Fiber can carry
more information with greater fidelity than copper.
Low attenuation and greater distance. Because
the fiber optic signal is made of light, very little signal
loss occurs during transmission, and data can move at
high speeds and greater distances. Fiber distances can
range from 300 meters (984.2 ft.) to 40 kilometers
(24.8 mi.), depending on the style of cable, wave-
length, and network. (Fiber distances are usually
measured in metric units.)
Security. Your data is safe with fiber. It doesn’t
radiate signals and is extremely difficult to tap. If
the cable is tapped, it leaks light causing failures.
Immunity. Fiber provides extremely reliable
data transmission. It’s completely immune to many
environmental factors that affect copper cable, such
as EMI/RFI, crosstalk, impedance, and more. You can
run fiber cable next to industrial equipment without
worry. It’s also less susceptible to temperature
fluctuations than copper cable is.
Design. Fiber is lightweight, thin, and more durable
than copper cable. It has pulling specifications that
are up to 10 times greater than copper cable. Its small
size makes it easier to handle, and it takes up less
space in cabling ducts. Like copper, fiber is available
with PVC and plenum jackets. Although fiber is more
difficult to terminate than copper, advancements in
connectors are making termination easier. And fiber
is actually easier to test than copper cable.
Costs. Installation costs for fiber are higher than
copper because of the skill needed for termination.
Overall, fiber is more expensive than copper in the
short run, but it may actually be less expensive in the
long run. Fiber typically costs less to maintain, has less
downtime, and requires less networking hardware.
Multimode vs. single-mode
There are two types of fiber cable: multimode
and single-mode. Most of the fiber cable used within
a building is multimode. Single-mode cable, with
its higher performance, is more commonly used
in campus networks between buildings.
Multimode, 50- and 62.5-micron cable.
Multimode cable has a large-diameter core and
multiple pathways of light. It comes in two core
sizes: 50-micron and 62.5-micron.
Cable jacket Aramid yarn Coating Cladding Core
Fiber Performance Standards
Attenuation Bandwidth Distance
Fiber Type Wavelength (dB/km) Max. (MHz/km) Gigabit Ethernet 10-GbE
Multimode
50-/125-Micron 850 nm 3.5 500 500 m 300 m
1300 nm 1.5 500 500 m 300 m
62.5-/125-Micron 850 nm 3.5 160 220 m 300 m
1300 nm 1.5 500 220 m 300 m
Single-Mode 8–10-/125-Micron
Premises 1310 nm 1.0 — 2–5 km* 10 km*
1550 nm 1.0 — 50–100 km* 40 km*
Outside Plant 1310 nm 0.5 — 2–5 km* 10 km*
1550 nm 0.5 — 50–100 km* 40 km*

13
Cabling
Multimode fiber cable can be used for most
general data and voice applications. Both 50-
and 62.5-micron cable feature the same cladding
diameter of 125 microns, but 50-micron fiber cable
features a smaller core (the light-carrying portion
of the fiber). LED and laser light sources can also
be used with both 50- and 62.5-micron cable.
The big difference between the two is that
50-micron cable provides longer link lengths and/or
higher speeds, particularly in the 850-nm wavelength.
Although both can be used in the same way,
50-micron cable is recommended for backbone,
horizontal, and intrabuilding connections, and
should be considered for any new construction and
installations. There is still a market for 62.5-micron
multimode products though because many buildings
already have multimode cable installed. But it bears
repeating: For new installations, use 50-micron cable.
Multimode fiber cable is traditionally orange.
50-micron fiber cable that’s optimized for 10-Gigabit
applications is aqua.
Single-mode, 8–10-micron cable. Single-mode
cable has a small 8–10-micron glass core and only
one pathway of light. With only a single wavelength
of light passing through its core, single-mode cable
realigns the light toward the center of the core
instead of simply bouncing it off the edge of
the core as multimode does.
Single-mode cable provides 50 times more
distance than multimode cable. Consequently,
single-mode cable is typically used in long-haul
network connections spread out over extended
areas, including cable television and campus
backbone applications. Telcos use it for connections
between switching offices.
Single-mode cable is traditionally yellow.
Specialty fiber cable.
Depending on your application, you may want
to use a specialty fiber cable.
To save money on innerducts and conduit, you
can use a fiber cable with an aluminum interlocking
armor covering an internal plenum jacket. It’s flexible
but extraordinarily strong so you can run this cable
anywhere in your building.
If you need to run cable outdoors, consider an
indoor/outdoor cable that can be pulled anywhere,
between and within buildings. Because of its tough
construction, it doesn’t have to be terminated within
50 feet of the building entrance. Outdoor fiber cable
is typically black.
Both cables are available at blackbox.com.
An aluminum interlocking
armor enables this
fiber cable to be run
anywhere indoors.
This tight-buffered cable
can be run anywhere—
indoors or out.
62.5 µm 125 µm
62.5-micron multimode
50 µm 125 µm
50-micron multimode
8–10 µm 125 µm
8–10-micron single-mode

Astructured cabling system, as defined
by the TIA/EIA, consists of six subsections:
Section Name
Section Name
Structured Cabling System
The structured cabling system
Horizontal Cabling
NOTE: This review is intended to present
only the highlights of applicable TIA/EIA
standards and is not to be considered
a definitive resource for planning your
system. For information on how you can
get the complete standards, see page 7.
1
Backbone Cabling
2
Telecommunications
Room (TR)
3
Work Area (WA)
4
Equipment Room (ER)
5
Entrance Facility (EF)
6

15
Horizontal cabling.
The horizontal cabling system encompasses everything
between the telecommunications room cross-connects to the
telecommunications outlets in the work area. It’s called horizontal
because the cable typically runs horizontally above the ceiling or
below the floor from the telecommunications room, which is
usually on the same floor. For details, see pages 16–18.
Backbone cabling.
The backbone system encompasses all the cabling between
telecommunications rooms, equipment rooms, entrance facilities,
and between buildings. For details, see pages 19–20.
Telecommunications room.
The telecommunications room holds the termination equipment
needed to connect the horizontal wiring to the backbone wiring.
A building must contain at least one telecommunications room,
and it should be on the floor it serves. For details, see page 22.
Work area.
The work area consists of all the components between the
telecommunications outlet and the user’s workstation equipment.
For details, see page 21.
Equipment room.
The equipment room houses telecommunications systems,
such as PBXs, servers, and the mechanical terminations. It’s different
than the telecommunications room because of the complexity
of the components. An equipment room may take the place of
a telecommunications room or it may be separate. For details,
see page 23.
Entrance facility.
The entrance facility is the point where the outdoor cable
connects with the building’s backbone cabling. This is usually the
demarcation point between the service provider and the customer-
owned systems. For details, see page 23.

Section Name
Section Name
5 m (16.4 ft.) maximum
Telecommunications room
Patch cable: 5 m
(16 ft.);
Total patch cable
on both ends:
10 m (32.8 ft.)
Telecommunications
outlet
Telecommunications
outlet
Telecommunications
outlet
Work area
90 m (295 ft.) maximum
Planning horizontal cabling.
The horizontal cabling system encompasses every-
thing between the telecommunications room cross-
connects to the outlets in the work area. It’s specified
in TIA/EIA-568-B.1 and includes:
• Horizontal cabling.
• Telecommunications outlets.
• Telecommunications connectors.
• Cross-connects.
• Patch cords.
• Consolidation point (if any).
Most of the cables in your building will be part of
the horizontal cabling system. These can include your
voice, data, multimedia, security, HVAC, PoE, wireless,
and other systems.
After a building is constructed, the horizontal
cabling system is subject to the most activity in
terms of users, locations, changes in building layouts,
and more. But the horizontal cable is much less
accessible than the backbone cable. To change the
horizontal cabling after installation can be very
expensive, time-consuming, and disruptive. Plan
carefully because the horizontal cabling is extremely
important to the design and effectiveness of your
cabling system.
Horizontal cabling considerations.
Change. Plan for it. Accept the fact that after
your system is up, most of the work will be MACs.
You should be able to relocate users and equipment
without changing the cable or disrupting users. Run
cable to all areas of the building, even if they’re
vacant. When expansion occurs, you’ll be ready.
Maintenance. Set up your system so that it
facilitates on-going maintenance.
Equipment. Satisfy current network requirements,
but consider future equipment changes, too.
Applications. Consider your current applications
while planning for more bandwidth-intensive
applications in the future.
User work areas. Don’t be surprised if your
organization decides to change its floor plan—
frequently. Just be prepared.
Keeping up appearances. To maintain a neat
office, horizontal cabling should never be visible.
There are many installation methods, including raised
access floor, conduit, cable trays, ceiling pathways,
raceways, and perimeter pathways.
Physical layouts. Consider how and where you’re
going to run cable. Do you have enough space to
Horizontal cabling
Work area
Work area
Horizontal Cabling Distances
Phone
Phone
Phone

17
4-pair, 100-ohm,
solid-conductor UTP cable
2- or 4-strand, 50- or
62.5-micron fiber optic cable
Small-form factor connectors
such as the LC, MT-RJ, and VF-45
SC
LC
ST
8-wire RJ-45
Maximum horizontal distances.
• Horizontal run: 90 meters (295.3 ft.) from the
telecommunications outlet to the horizontal
cross-connect.
• Work-area patch cord: 5 meters (16.4 ft.).
• Total of work-area and cross-connect patch cords,
equipment cables, jumpers, etc: 10 meters (32.8 ft.).
Recognized media.
Cables
You can use these cables individually or in
combination.
• 4-pair, 100-ohm UTP or ScTP cable (24 AWG,
solid conductors) (EIA/TIA-568-B.2).
• 2-fiber (or more) 50- and 62.5-micron
fiber optic cable (EIA/TIA-568-B.3).
• 150-ohm shielded twisted-pair cable
is recognized, but not recommended.
Hybrid cables (multiple cable types in one
sheath) are allowed, provided each individual cable
is recognized and meets the transmission and color-
coding requirements for that cable.
For copper horizontal runs, use solid-conductor
cable. Use stranded conductor cable for the patch
cords. Make sure your cables are marked with
the correct performance category. And match
performance categories of the channel equipment,
such as jacks, patch cords, patch panels, etc.
This ensures category performance.
Connectors
• 8-position modular jack and plug with T568A
or T568B pinning. See page 21.
• SC and ST®
fiber connectors.
• Small form-factor fiber connectors.
accommodate bend radius and fill ratios? What
are fire and building code regulations? Are there
physical barriers or environmental factors, such as
seismic planning or water levels? You get the idea.
Documentation. Plan on thoroughly labeling and
documenting all connections in the telecommunica-
tions room and at the workstation outlet.
EMI. Take into account any areas of high EMI,
such as near elevators, motors, and other equipment.
Horizontal topology.
The following are highlights of the TIA/EIA-568-
B.1 specifications.
• The horizontal system shall (remember that
“shall” means required) be installed in a star
topology.
• Each work-area telecommunications outlet shall
be connected to the horizontal cross-connect
in the telecommunications room.
• The telecommunications room should
be on the same floor as the work area.
• Bridge taps and splices shall not be installed
for copper cable.
• No more than one transition point or
consolidation point shall be installed.
(The exception comes later.)
• Electrical components shall not be installed as
part of the horizontal cabling. No application-
specific components can go there either. They
can go next to the outlets or cross-connects.
• A minimum of two telecommunications
outlets shall be installed for each work area.
One should be at least CAT3 or higher for voice.
The other should be CAT5e or higher for data.
You can add more if you want.

Consolidation
point
Horizontal cabling
horizontal cross-connect
To equipment
Work area
cables
Open office area
Consolidation Point
To equipment
Open office area
Horizontal cabling
Section Name
Section Name
Open office cabling.
If you have an open office with lots of modular
furniture and anticipate lots of MACs, the TIA has
specified two horizontal cabling configurations for
you: the MUTOA and the Consolidation Point. Both
will enable you to keep your horizontal cabling
intact when your open office layout is changed.
Open office cabling is the only exception you’ll
find to the 5-meter rule for work area cables.
Open Office Horizontal Cabling Distances
Work Area, Patch, and
Horizontal Cable Maximum Work Area Equipment Cord Maximum
Length Cable Length (24 AWG) Combined Length
90 m (295.3 ft.) 5 m (16.4 ft.) 10 m (32.8 ft.)
85 m (278.9 ft.) 9 m (29.5 ft.) 14 m (45.9 ft.)
80 m (262.5 ft.) 13 m (42.6 ft.) 18 m (59.1 ft.)
75 m (246.1 ft.) 17 m (55.7 ft.) 22 m (72.1 ft.)
70 m (229.6 ft.) 22 m (72.1 ft.) 27 m (88.6 ft.)
MUTOA (Multiuser Telecommunications Outlet Assembly).
The MUTOA enables the terminations of multiple
horizontal cables in a common, permanent location,
such as a column, wall, or permanent furniture, close
to a cluster of work areas. Guidelines include:
• Locate multi-user telecommunications outlets
in a permanent location.
• Multi-user telecommunications outlets shall
not be installed in the ceiling.
• The maximum cable length is 20 meters (65.6 ft.).
• A maximum of 12 work areas can be served.
• Uniquely identify work area cables on each end.
Consolidation point.
The Consolidation Point (CP) is a straight-through
interconnection point in the horizontal cabling.
It provides another option for open office cabling
and is ideal for work areas that are frequently
reconfigured, but not as frequently as a MUTOA.
Specifications include:
• Only one CP is allowed per horizontal run
between the work area and telecommunications
room. Cross-connection between the cables
is not allowed.
• A CP should not be more than 15 meters (49.2 ft.)
from the telecommunications room.
• A CP can serve a maximum of 12 work areas.
Centralized fiber optic cabling.
Centralized fiber optic cabling, Annex A to the
TIA/EIA-568-B.1, gives you recommendations for
designing a fiber-to-the-desktop system. It centralizes
the fiber electronics instead of using electronics on
different floors. Recommendations include:
• To connect the fiber from the work area to the
equipment room, you can use either a splice or
interconnect in the telecommunications room.
• The distance for the total channel is 300 meters
(984.3 ft.), including the horizontal, intrabuilding
backbone, and patch cords.
• Fiber can be pulled through the telecommunications
room. The distance is limited to 90 meters (295.3 ft.).
• Cable can be 50- or 62.5-micron fiber.
• Allow for slack and sufficient space for the
addition and removal of cable, and conversion
to a full cross-connect system.
Work area
cables
MUTOA
horizontal cross-connect
NOTE: The maximum length for a work area cable is 22 meters (72.1 ft).
For fiber cable, any combination of horizontal, work area, patch,
and equipment cables may not exceed 100 meters (328 ft).
MUTOA

19
Planning backbone cabling.
Backbone cabling provides the main information
conduit connecting all your horizontal cabling within
a building and between buildings. It’s the inter-
connection between telecommunication rooms,
equipment rooms, and entrance facilities. In large
organizations, you can connect multiple LANs with
a high-speed backbone to create large service areas.
Backbone cabling is specified in TIA/EIA-568-B.1
and includes:
• Cabling
• Intermediate and main cross-connects
• Mechanical terminations
• Patch cords or jumpers for backbone-
to-backbone connections
Another type of backbone is called a collapsed
backbone. This is usually a short backbone that has a
central router or switch interconnecting all the LAN
segments in a given building.
The main requirement of any backbone is that
it be able to support your current needs as well as
future applications. When planning your backbone,
take these factors into consideration.
Performance and applications. Plan on far more
bandwidth than you think you’ll ever need.
Site size and user population. Current size and
future growth requirements must be considered.
Plan your backbone to accommodate the maximum
number of connections anticipated in all telecommun-
ications rooms, equipment rooms, and entrance
facilities. You may want to consider installing extra,
unused copper or ”dark” fiber cable for future needs.
Distance. The distance you run your backbone will
most likely determine the type(s) of cable you use.
Redundancy and diverse path routing. Consider
diverse path routing for mission-critical systems. This
consists of running redundant backbones in separate
pathways far from each other. The redundant cables
should never be run in the same conduit. Although
they terminate at the same place, they will follow
different routes to get there, such as on different
sides of a building.
Useful life. Be aware of the minimum length
of time the backbone cabling is expected to serve.
Replacing backbone cable is inconvenient and
expensive.
Entrance facility
Work area
2000 m (6561.7 ft.)
campus backbone
Backbone Cabling Distances
Backbone cabling
Building 2
Entrance facility
Building 1
90 m (295.3 ft.)
horizontal cabling
300 m (984.3 ft.) building
backbone cabling

Backbone Cabling Distances
Main Cross-Connect to Main Cross-Connect to Intermediate Cross-Connect
Media Type Horizontal Cross-Connect Intermediate Cross-Connect to Horizontal Cross-Connect
100-ohm Copper 800 m (2624.7 ft.) 500 m (1640.4 ft.) 300 m (984.3 ft.)
Multimode Fiber 2000 m (6561.7 ft.) 1700 m (5577.4 ft.) 300 m (984.3 ft.)
Single-mode Fiber 3000 m (9842.5 ft.) 2700 m (8858.3 ft.) 300 m (984.3 ft.)
Physical environment.
– EMI. Install copper away from areas of EMI.
– Physical plant systems. Install away from
a building’s physical plant systems, such as
electrical wiring, plumbing, and sprinklers.
Do not install backbone cable in elevator shafts.
– Environment. Air spaces should be examined
for dampness, which can corrode copper cable.
In addition, take into account all pathway
standards and requirements.
– Fire resistance. Pay attention to all fire
regulations.
– Security. Make sure your backbone cable and
all equipment and telecommunications rooms
are inaccessible to unauthorized personnel.
Backbone topology.
The recommended topology is a conventional
hierarchical star where all the wiring radiates from
Backbone cable
Equipment room
intermediate cross-connect
To work area via horizontal cable
a central location called the main cross-connect. Each
telecommunications room or equipment room is
cabled to the main cross-connect either directly or via
an intermediate cross-connect. A benefit of this
topology
is that it provides damage control. If a cable goes out,
only that segment is involved. Others are unaffected.
Here are some backbone cabling recommendations:
• The backbone system shall be installed in a
hierarchical star topology.
• From the horizontal cross-connect, there shall
be no more than one additional cross-connect
to reach the main cross-connect.
• There should be no more than two levels
of backbone cross-connects.
• There shall be no bridged taps and splitters.
• Make sure you meet all grounding requirements.
Recognized media.
The cable you choose depends on your application
and distance requirements. Fiber and copper cables
have different characteristics that may make one
more suitable for a particular application over the
other. You may even use a combination of the two.
For instance, you can use fiber to connect runs
between buildings and for the vertical riser within
a building. But you may decide to use copper for the
second level backbone connecting the intermediate
cross-connects to the horizontal cross-connects.
Recognized cables include:
• 4-pair, 100-ohm twisted-pair cable
(TIA/EIA-568-B.2).
• 50- or 62.5-micron multimode fiber optic cable
(TIA/EIA-568-B.3).
• Single-mode fiber optic cable (TIA/EIA-568-B.3).
Maximum distances.
Backbone cable distances depend on the
application as well as the cable used. For allowed
distances, see the chart below .
Equipment room
main cross-connect
To work area via horizontal cable
Backbone cable
Backbone cable
Backbone Topology

Wiring Color Codes
Wire Color Pair Tip/Ring T568A Jack Pin # T568B Jack Pin #
White/Blue 1 Tip 1 5 5
Blue/White 1 Ring 1 4 4
White/Orange 2 Tip 2 3 1
Orange/White 2 Ring 2 6 2
White/Green 3 Tip 3 1 3
Green/White 3 Ring 3 2 6
White/Brown 4 Tip 4 7 7
Brown/White 4 Ring 4 8 8
21
Work area
The work area consists of all the components
between the telecommunications outlet and the
user’s desktop workstation equipment. This covers:
• Telecommunications outlets, including
wallplates, faceplates, surface-mount boxes, etc.
• Patch cables.
• Adapters, including connectors, and modular
jacks.
• Workstation equipment, such as PCs, telephones,
printers, etc. although they aren’t included in
the standard.
The work area should be well managed even
though it is designed for frequent changes. There are
a few specific recommendations in TIA/EIA-568-B.1:
• You should install a minimum of two tele-
communications outlets in each work area.
– The first outlet shall be a 100-ohm,
8-position modular jack, CAT3 or higher.
It’s very advisable to use CAT5e or higher.
– The second outlet can be another 100-ohm,
8-position modular jack (minimum CAT5e
or CAT6), or...
– A 2-fiber, 62.5- or 50-micron fiber SC, ST,
or other small-form factor duplex fiber
connector.
• UTP wiring should follow T568A or T568B
schemes. (See right.)
• The 4-pair UTP patch cable from the
telecommunications outlet to the workstation
equipment should be no more than 5 meters
(16.4 ft.).
• Make sure the equipment cords, patch
cables, and modular jacks all have the
same performance rating.
• Follow standard installation practices and
maintain proper pair twists, bend radius, etc.
• Use different pathways for electrical wiring
and structured cabling.
• Estimate pathway capacity at 20–40% fill.
• Run an independent pathway to control centers,
reception areas, and other high-activity spaces.
• An electrical outlet should be installed within
3 feet (9.1 m) and at the same height.
T568A and T568B pinning.
There are two approved pinning methods: T568A
and T568B. The T568A scheme is the one recognized
and used by the U.S. government. The T568A pinning
is also common in Canada and in other parts of the
world.
The T568B pinning is the one used by AT&T®
and
is the de facto standard in the U.S.
By the way, the T stands for termination, and not
TIA as commonly thought.
Whichever scheme you choose, stick to it. All
pin/pair assignments must conform to one standard
or the other. Mixing the two can cause crossed pairs,
which just doesn’t work. In addition, you must follow
established telecommunications cabling color
schemes.
T568A
T568B
Pair 1
Pair 2
Pair 3
Pair 4

Recommended Room Sizes
Floor Area Room Size
m2
ft.2
m ft.
1000 10,763 3 x 3.4 10 x 11
800 8611 3 x 2.8 10 x 9
500 5381 3 x 2.2 10 x 7
TECH TIP
A cross-connect is the
connection between
horizontal cabling and
backbone or equipment
hardware. Connections
made directly between
equipment and the
horizontal cable are
called interconnects.
Typical Layout of a Telecommunications Room
Typical layout of
telecommunications closet
This is Straight pickup from old
guide
36" x 80"
door with
lock
Instrument power
Equipment power
Equipment rack Equipment rack
Closet
interconnecting
conduit
(fire stopped)
Ceiling level ladder rack
Fluorescent ceiling fixtures
4" sleeves (minimum)
Equipment power
21 mm
(trade size 3
⁄4 in.)
plywood
backboard
• At least two walls must be covered in 2.6-meter
(8.5-ft.) high, 200-mm (3
⁄4 in.) thick A–C plywood
capable of supporting equipment.
• Do not install a false ceiling.
• Lighting should supply at least 500-foot candles
(540 lux) of illumination.
• Walls, floor, and ceiling should be light colored
to enhance lighting.
• HVAC equipment should provide continuous
24/7/365 service.
• Fire protection should be provided.
• The door should be at least 910-mm (35.8-in.) wide
and 2000 millimeters (78.75 in.) high. It should be
hinged, sliding, or removable, and have a lock.
• The minimum floor loading should be at least
2.4 kPa (50lbf/ft2
).
• Install at least two dedicated duplex electrical outlets
on separate circuits. If necessary, additional duplex
outlets can be placed at 1.8 meters (5.9 ft.) around
the room.
Section Name
Section Name
• Depending on the size of the floor area, you
should have at least one telecommunications
room per floor. The recommendation is one TR
per 10 m2
(100 ft.2
).
• If the floor area is greater than 1000 m2
(10,763 ft.2
), or if the distance to the work area
exceeds 300 feet, there should be additional
telecommunications rooms per floor.
• When there are multiple telecommunications
rooms on a floor, interconnect them with at
least one trade size 3 conduit.
• Specific room sizes are recommended based
on floor-area size. These provide sufficient space
for all connecting hardware, as well as enough
room for technicians to work comfortably.
• Be aware of any seismic zone requirements.
Formerly known as the telecommunications closet,
the telecommunications room (TR) houses all the
equipment associated with connecting the backbone
wiring to the horizontal wiring. It includes:
• Intermediate cross-connects
• Main cross-connects
• Patch cords
• All connecting equipment
The telecommunications room can also house
auxiliary equipment such as a PBX, security
equipment, etc.
Design specifications.
The telecommunications room is addressed in
TIA/EIA-568-B.1. But you’ll find the complete design
and provisioning recommendations in TIA/EIA-569-B.
• If you’re terminating less than 100 meters of
cable, you can use an interconnection. As the
number of connections grows, use cross-connects
for better cable management.
• Place the telecommunications room as close
as possible to the center of the floor.
• Do not share the telecommunications room
with electrical equipment.
Requirements for the Telecommunications Room

23
Equipment room
The equipment room (ER) houses tele-
communications systems, such as PBXs, servers,
routers, switches, and other core electronic
components as well as the mechanical terminations.
It’s different than the telecommunications room
because of the complexity of the components.
An equipment room may take the place of a
telecommunications room or it may be separate.
It can also function as the entrance facility. The
equipment room is specified in TIA/EIA-568-B.
Design recommendations are in TIA/EIA-569-B.
Design considerations.
• Each building should contain at least one
equipment room or telecommunications room.
• Only install equipment related to the
telecommunications system.
• Consider future expansion when sizing and
placing the equipment room.
• Design the door to accommodate the delivery
of large enclosures and equipment. The door
should be a minimum of 910 mm (35.8 in.) wide
and 2000 mm (78.7 in.) high. A double door
without a center post is best.
• The minimum ceiling height shall be 2.4 meters
(7.8 ft.). No false ceilings either.
• The minimum recommended size is 14 m2
(150.7 ft.2
). The general rule is to allow 0.07 m2
(0.75 ft.2
) for every 10 m2
(107.6 ft.2
) of usable
floor space.
• The room should have conditioned power
and backup power.
• Protect against vibration, EMI, contaminants,
and pollutants. The room should not be near
mechanical rooms, electrical distribution panels,
and wet/dirty areas.
• Take into account any water infiltration issues.
Do not locate the room below water level.
• Like the telecommunications room, provide
24/7/365 HVAC. Temperature and humidity
should be controlled.
• The lighting should be the same as the TR:
500 lux (50 foot candles).
• The floor loading should be a minimum
of 4.8 kPa (100 lbf/ft2
).
Entrance facility
The entrance facility (EF) is the point where the
outdoor plant cable connects with the building’s
backbone cabling. This is usually the demarcation
point between the service provider and the customer-
owned systems. The entrance facility is designated
in TIA/EIA-568-B. Design recommendations are in
TIA/EIA-569-B. It includes:
• Cables.
• Connecting hardware.
• Protection devices.
Design considerations.
• The entrance facility may also house the
backbone links to other buildings in a campus.
• Public network interface equipment and
telecommunications equipment may be
in the entrance facility.
• The location should be a dry area, near the
vertical backbone pathways.
• The entrance facility should be provisioned
as the telecommunications room is for
environment, HVAC, lighting, doors,
electrical power, etc.
Backbone cabling
Equipment room
main cross-connect
Entrance facility
main cross-connect
Backbone
cabling
Entrance Facility and Equipment Room

Section Name
Section Name
Simply put, a pathway is the space in which
cable runs from one area to another. The standard
TIA/EIA-569-B: Commercial Building Standard for
Telecommunications Pathways and Spaces defines
different types of pathways, such as interbuilding,
intrabuilding, horizontal, service entry, etc.
This discussion will cover intrabuilding backbone
and horizontal pathways. Interbuilding and service
entry pathways are beyond the scope of this guide.
Intrabuilding backbone pathways.
Intrabuilding backbone pathways run vertically
and horizontally between the entrance facilities,
equipment room, and telecommunications room(s).
They carry the backbone cable and can be conduit,
sleeves, slots, or cable trays. Complete specifications
for conduit, sleeves, trays, pull points, and more can
be found in the TIA standard.
NOTE: Make sure all pathways are firestopped.
And, do not use elevator shafts as backbone pathways.
Vertical backbone pathways. When designing
a building, stack the telecommunications rooms
vertically above one another on each floor. This
provides for the easiest and most efficient backbone
runs. The TRs should have a minimum of three 4-inch
sleeves for floor areas of 5000 m2
(58,819 ft.2
). One
sleeve is for the cable; the other two are spares.
Horizontal backbone pathways. If the TRs are not
stacked vertically, use 4-inch conduit to connect them
horizontally. You should have no more than two 90°
bends between pull points. In addition, the fill should
not exceed 40% for any run greater than two cables.
Horizontal pathways.
As the name suggests, these pathways run
horizontally between the telecommunications room
and the work area. You can choose a number of
different pathways, depending on your facility, office
layout, and cable type. When choosing, keep in mind
the pathway fill for current and future use, and allow
enough room for growth.
Pathway options.
Underfloor duct. These are a system of single- or
dual-level, rectangular ducts embedded in concrete
flooring that’s at least 64-mm (2.5-in.) or 100-mm
(3.9 in.) deep, respectively.
Flush duct. This is a single-level, rectangular duct
embedded flush with the top level of a 25-mm (1-in.)
concrete surface.
Multichannel raceway. Ducts have separate
channels for running telecommunications and power
cable. The raceways are designed to be buried in
75-mm (3-in.) reinforced concrete.
Pathways
Building Pathways
Backbone pathways
Equipment
room
Work area
Entrance facility
Horizontal pathways

Cable duct
25
Cellular floor. These are preformed, steel-lined
cells buried in 75-mm (3-in.) reinforced concrete.
They come with preset fittings and large capacity
header ducts.
Trench duct. This solid tray has compartments and
a flat top, and is embedded flush with the concrete.
Access floor. This consists of modular floor panels
supported by pedestals. It’s commonly used in
computer and equipment rooms.
Conduit. There are different types of conduit:
metallic tubing, rigid metal, and rigid PVC. Use
conduit when your telecommunications outlets are
considered permanent, device density is low, and
future changes are not a consideration. Conduit must
meet the appropriate electrical codes. It should not
be longer than 30 meters (98.4 ft.) nor contain more
than two 90-degree bends between pull points.
Cable trays. Options include prefabricated
channel, ladder, solid bottom, ventilated, and wire
trays. Trays can be located above or below the ceiling.
Ceiling pathways. This is one of the most popular
methods of routing cable. Bundled cables run on
J-hooks suspended above a plenum ceiling. The
cables are then fanned out through the walls,
support columns, or power poles to the work area
outlet. Cables must be supported and must not be
run directly on the ceiling tiles.
Perimeter raceways. These include plastic or
metal surface, recessed, multichannel, and molded
raceways. Use them in areas where devices can
be reached from the walls at convenient levels.
Fill capacity should be no more than 20–40%,
depending on the cable.
Power considerations.
Make sure your telecommunications cables and
power cables are separated. Also check your local
codes. Some allow the two cables to be run in the
same raceway (with a barrier), while others do not.
Consider sources of EMI/RFI and be sure to use surge
protection equipment.
Other pathways.
Please refer to the standard for recommendations
for work area and telecommunications outlet
pathways.
Perimeter raceway
Cable tray
Cable raceway

Tension.
Too much tension will give you a headache.
UTP. To avoid stretching, pulling tension should
not exceed 110 N (25 lb/ft.). Pulling too hard untwists
the pairs, and you know what that does. Use supports
and trays in cable runs to minimize sagging, which
pulls on the pairs and degrades performance.
2- and 4-fiber horizontal: The maximum tensile
load is 222 N (50 lb/ft.).
Cinching.
Take care not to cinch cable bundles tightly, which
causes stress and degrades performance. Tie cable
bundles loosely. And never ever staple cables.
Connecting hardware.
Twisted pair. It may seem obvious, but use
connecting hardware of the same category or higher.
The transmission of your components will always be
the lowest category in the link. So, if you’re using
CAT6 cable, use CAT6 connectors.
Fiber. Fiber is much more difficult to terminate
in the field than copper cable. If you have a poor
fiber polish and alignment, you’ll lose a great deal
of performance. Rather than field polishing the
termination, use pre-polished connectors.
Miscellaneous considerations.
• Visually inspect the cable installation for proper
terminations, bend radius, tension, etc.
• Don’t uncoil UTP on a spool. It can cause kinks
and NEXT failures. Rotate the spool instead.
• Plan for 12 inches of slack cable behind wall outlets
for possible future reterminations.
• As always, avoid EMI. And don’t run UTP cable over
fluorescent lights, etc.
You can invest in the best cable and hardware, but
if they’re not installed properly, they won’t work, or
at least they won’t work well. Protect your investment
and follow the guidelines as outlined in TIA/EIA-568-B.1.
The most important practices involve:
1. Cable pair twists.
2. Bend radius.
3. Tension.
4. Cinching.
5. Connecting hardware.
There are others, but if you do nothing else,
mind these.
Cable pair twists.
This is the most important guideline you can
follow for twisted-pair cable. The
pair twists are responsible for much
of cable’s performance. If you lose
the twists, you lose performance.
Remember this.
When terminating CAT5e or
higher, maintain pair twists to
within 13 mm (0.5 in.) from the
point of termination. And remove
as little of the sheath as possible.
Bend radius.
Next on your installation ”to-do” list is bend
radius. If you bend twisted-pair cable too much, you
loosen the twists, and yes, lose performance. The
following bend radii are under no-load conditions:
UTP horizontal. 4 times the cable diameter.
ScTP horizontal. 8 times the
cable diameter.
Multipair backbone. 10 times
the cable diameter.
2- and 4-fiber horizontal.
Not less than 25 mm (0.98 in.).
Fiber backbone: Not less than
10 times the cable diameter, or as
recommended by the manufacturer.
Even though there is no standard
at this time for patch cable bend
radius, be aware of that, too.
Section Name
Section Name
Installation &Testing
Cable installation practices
UTP bend radius = 4X cable diameter
Observe proper bend radius.
0.5"
(13 mm)
Keep jacket removal
and untwists to a minimum.
Keep cable wraps snug
but do not pull or crush cables.

27
Installation &Testing
Work area
equipment cable:
Up to 5 m (16.4 ft.)
Channel and Permanent Link
Optional
consolidation
point
Cable testing
Once you install your structured cabling infrastructure,
you have to test its performance. Just because you
bought the best materials and followed all the
installation recommendations, it doesn’t mean your
system is going to work flawlessly. Transmission
performance depends on a number of factors:
– Cable characteristics
– Connecting hardware
– Patch cords and cross-connect wiring
– Number of connections
– Installation practices
Specific performance requirements are listed
in TIA/EIA-568-B.2 for balanced twisted-pair cable
and TIA/EIA-568-B.3 for fiber optic cable.
Field testing copper.
There are two ways to check a copper cabling
system: channel tests and permanent link tests.
Channel. This provides the most reliable results
for actual transmission performance. Channel tests
are performed after all the telecommunications
equipment is in place. The channel includes:
– Horizontal cable, up to 90 meters (295.3 ft.)
– Work area patch cord, up to 5 meters (16.4 ft.)
– Work area telecommunications outlet connector
– Optional consolidation point connection
– Two TR patch cord connections
The total length of the channel must not exceed
100 meters (328 ft.). The total length of equipment,
patch, and work area cords must not exceed
10 meters (33 ft.).
Many manufacturers now have their channels
pre-tested and verified by independent laboratories,
such as ETL®
Semko.
Permanent link test. This test provides installers
and technicians with a method of verifying the
performance of the permanently installed cable,
minus any patch cord connections. It measures
performance before any telecommunications room
equipment or office furniture is installed, and is not
as accurate as the channel test. The permanent link
includes:
– Horizontal cable, up to 90 meters (295.3 ft.)
– Two connections, one at each end
– An optional consolidation point connection
Copper test parameters.
The primary copper test parameters are:
– Wire map – Return loss
– Length – Propagation delay
– Insertion loss – Delay skew
– Near-end crosstalk (NEXT)
– Power-sum near-end crosstalk (PS-NEXT)
– Equal-level far-end crosstalk (EL-FEXT)
– Power-sum equal-level far-end crosstalk (PS-ELFEXT)
For explanations, see the Glossary on pages 41–43.
For more copper performance parameters and
10-GbE test information, see pages 28–29.
Patch panel
Patch panel cords: total
of work area and patch
cords not to exceed 10 m
(32.8 ft.)
Permanent link: 90 m (295.3 ft.)
Channel: 100 m (328.1 ft.)

Section Name
Section Name
Installation & Testing
Copper testers.
If all these tests seem a little overwhelming,
they are. But there’s help—professional technicians
and professional-grade test equipment. Trained
technicians know how to use the advanced Level III
and IV equipment that automatically tests, calculates,
and certifies your copper cable links in accordance
with TIA and ISO standards. Level III equipment is
designed for measurements to 250 MHz. Level IV
testers certify accuracy up to 600 MHz. Manufacturers
of test equipment are conforming to the changes in
standards with firmware updates.
The results of the tests will tell you if your system
meets all the applicable performance standards.
If there are problems, the technicians and the
* ACRF (Attenuation to crosstalk ratio, far-end) is replacing ELFEXT
in the CAT6a proposed draft.
** PSACR-F (Power sum attenuation to crosstalk ratio, far end) is replacing
PS-ELFEXT in the CAT6a proposed draft.
NOTE: PS-ANEXT (power sum alien near-end crosstalk) and PS-AACRF (power
sum attenuation-to-alien crosstalk ratio, far-end) are new measurements.
Copper Performance Comparison at 100 MHz
CAT5e CAT6 CAT6a ISO Class F (CAT7)
Standard TIA-568-B.2 TIA-568-B.2-1 TIA-568-B.2-10 ISO/IEC
draft 11180*
Insertion Loss
Channel 24.0 dB 21.3 dB 20.8 dB 20.8 dB
Permanent Link 21.0 dB 18.6 dB 17.9 dB 17.7 dB
NEXT
PS-NEXT
ELFEXT (ACRF*)
PS-ELFEXT (PSACR-F**)
Return Loss
PS-ANEXT
Channel — — 60.0 dB —
Permanent Link — — 61.1 dB —
PS-AACRF
Channel — — 37.0 dB —
Permanent Link — — 37.8 dB —
equipment can help isolate the problem. Better
yet, the equipment saves all the test results for
downloading and proper documentation.
10-GbE considerations.
In June 2006, the IEEE approved the standard for
10-Gbps Ethernet, or 10GBASE-T (10-GbE). 10-GbE
transmission requires a bandwidth of 500 MHz. The
industry is using two different cables for 10-GbE
applications: Category 6 (CAT6) cable and
Augmented Category 6 (CAT6a).
Alien crosstalk.
Before discussing how to test CAT6 and CAT6a
in 10-GbE, a definition of alien crosstalk is needed.
Alien crosstalk (ANEXT) is a critical measurement
unique to 10-GbE systems. Crosstalk, measured in
10/100/1000BASE-T systems, is the mixing of signals
between wire pairs within a cable. Alien crosstalk
is the measurement of the signal coupling between
wire pairs in different, adjacent cables.
The amount of ANEXT depends on a number of
factors, including the proximity of adjacent cables
and connectors, cable length, cable twist density, and
EMI. Patch panels and connecting hardware are also
affected by ANEXT.
With ANEXT, the affected cable is called the
disturbed, or victim, cable. The surrounding cables
are the disturbers.
10-GbE over CAT6.
CAT6 cable must meet 10-GbE electrical and
ANEXT specifications up to 500 MHz. However, as of
mid 2007, the CAT6 standard specifies measurements
only to 250 MHz and does not specify an ANEXT
requirement. There is no guarantee CAT6 can support
a 10-GbE system. But the TIA TSB-155, ISO/IEC 24750,
and IEEE 802.3an all characterize 10GBASE-T over UTP
cabling.
The TSB provides guidelines for ways to help
mitigate ANEXT. One way to lessen or completely
eliminate ANEXT is to use shielded equipment and
cables such as Black Box’s S/FTP or F/UTP cables (see
blackbox.com). Another way is to follow mitigation
guidelines, such as using non-adjacent patch panels,
separating equipment cords, unbundling cabling, etc.

29
Installation & Testing
10-GbE over CAT6a.
Augmented Category 6 (CAT6a) and Augmented
Class E (Class EA) cabling are designed to support
10-GbE over a 100-meter horizontal channel.
The TIA/EIA-568B.2-AD10 (draft) extends CAT6
electrical parameters such as NEXT, FEXT, return loss,
insertion loss, and more to 500 MHz. The CAT6a draft
specifies near- and far-end alien crosstalk (ANEXT,
AFEXT) to 500 MHz for closely bundled “six around
one” cable configurations. It also goes beyond IEEE
802.3an by establishing the electrical requirements
for the permanent link and cabling components.
The ISO Class EA standard will be published in a
new edition of the 11801 standard.
These standards specify requirements for
each component in the channel, such as cable and
connecting hardware, as well as for the permanent
link and the channel.
Testing 10-GbE.
Field certification for 10-GbE consists of two
phases. The first is to certify the transmission
capability and quality of each individual link. The
10-GbE test limits are identical to CAT6 and ISO 11801,
but the frequency range is extended from 250 MHz
to 500 MHz. The parameters are insertion loss, return
loss, pair-to-pair near-end crosstalk (NEXT), power-
sum NEXT, pair-to-pair equal-level far-end crosstalk
(ELFEXT), Power-Sum ELFEXT (PS-ELFEXT), propaga-
tion delay, length, delay skew, and wire map.
The second phase is to field certify the cabling
system for compliance with alien crosstalk (ANEXT)
requirements, which are the between-channel
parameters. This should include sample testing
of some links in a bundle to verify compliance.
Measuring ANEXT.
Typically in a laboratory, measuring power sum
alien near-end crosstalk (PS-ANEXT) and power-sum
alien far-end crosstalk (PS-AFEXT) is based on cables
in a “six-round-one” configuration. The central cable
is the victim cable, and all the adjacent cables are the
disturbers. This test configuration provides a worst
case scenario. A total of seven equal length links
are connected to each other at previously defined
distances. Every circuit is measured against the other
so there are 96 individual measurements.
At this point, it's not possible to test all wire-pair
combinations in the field for ANEXT. One strategy
is to use a sampling technique to select a limited
number of links for testing. The chosen links should
be those most likely to fail, such as the longest links,
or shorter links with the shortest distance between
connectors. Limit testing to links that are bundled
together.
Field testing fiber.
Compared to copper, fiber optic cable is relatively
simple to test. Basically, you shine a light down the
cable and measure how much arrives on the other
end. That’s attenuation, and it’s the performance
parameter used for fiber testing. Unfortunately,
attenuation can be affected by the installation,
but it’s easily tested in the field.
The typical fiber test link includes:
– Fiber cable (horizontal or backbone, depending
on application)
– Telecommunications outlet connector
– Consolidation points, if any
When testing fiber, each individual link segment
in both the horizontal and backbone runs must
be tested. Each segment is allowed a budget loss.
Then, the total link insertion loss is the sum of the
individual link segment losses.
The performance standards for fiber optic cable
are listed in the chart on page 12.
Fiber testers.
Don’t worry about trying to test your fiber
system yourself. Again, there are professional
technicians who know how to use advanced fiber test
equipment, which includes a power meter and a light
source. Very advanced equipment can test different
wavelengths, in both directions, eliminating a lot of
legwork for either you or a professional technician.
These testers, like their copper counterparts,
automatically calculate all test results and save
them for future downloading and documentation.
TECH TIP
In a six-around-one
configuration with a
disturbed, or victim,
cable, alien crosstalk
measures the crosstalk
induced in a wire pair
in the victim cable by
wire pairs in adjacent
cables. ANEXT can be
mitigated or eliminated
through the use of
S/FTP or F/UTP cable.
ANEXT

Section Name
Section Name
Other Standards
Following standard practices ensures current and future
occupants of a building have all the information they need for
smooth operations. Administrative record keeping is detailed
in TIA/EIA-606-A: Administration Standard for Commercial
Telecommunications Infrastructure. It specifies identification,
labeling, and documentation for different components of the
structured cabling system, including:
• Telecommunications pathways (horizontal and backbone)
• Telecommunications spaces (telecommunications rooms,
work areas, equipment rooms, etc.)
• Connecting hardware and splices
• Cables
• Equipment
• Building(s)
• Grounding and bonding
Classes of administration.
The TIA specifies four classes of administration based on
the size and complexity of the infrastructure. It defines the
requirements for identifiers, records, and labeling.
Class 1: Single equipment room. This is a building with
a single equipment room and no backbone cabling.
– Telecommunications Space (TS) identifier
– Horizontal link identifier
– Telecommunications Main Grounding Busbar (TMGB)
– Telecommunications Grounding Busbar (TGB)
Class 2: Single building, multiple telecommunications rooms.
– Class 1 identifiers
– Building backbone identifier
– Building backbone pair or fiber identifier
– Firestopping location identifier
– Optional pathways identifiers
Class 3: Campus with multiple buildings.
– Class 2 identifiers
– Building identifier
– Campus backbone cable identifier
– Campus backbone pair or fiber identifier
Optional identifiers:
– Optional Class 2 identifiers
– Outside plant pathway element identifier
– Campus pathway or element identifier
Additional identifiers may be added.
Structured cabling administration
Class 4: Multisite/multicampus.
– Class 3 identifiers.
– Campus or site identifier
Optional identifiers:
– Optional Class 3 identifiers
– Intercampus element identifier
Additional identifiers for mission-critical systems, WAN
connections, large or multitenant buildings, pathways and spaces,
and outside plant elements are optional, but recommended.
Identification formats/labeling.
When identifying the elements in your system, you must create
a unique alphanumeric code, or label, for each location, pathway,
cable, and termination point. These codes link back to the
corresponding record, which should contain all the information
related to that component, including linkages.
The format of the code or label is not mandated by the
standard, although it does list numerous examples. Whatever
format you choose, it must be consistent, logical, and flexible.
The label itself must be easily readable and should withstand
environmental conditions. The labels must be printed or produced
mechanically.
Color coding.
Color coding the termination fields is recommended to simplify
system administration. A rule of thumb is that the labels identifying
each end of a cable must be the same color.
Pantone Element
Color Number Identified
Orange 150C Demarcation point
(central-office termination)
Green 353C Network connections
on the customer side
Purple 264C Common equipment
White First-level backbone
Gray 422C Second-level backbone
Blue 291C Horizontal cabling terminations
Brown 465C Interbuilding backbone
Yellow 101C Auxiliary circuits
Red 184C Key telephone systems
Label Color Coding

First IP Number
0 No protection
1 Protection from solid foreign objects
of 50 millimeters or greater
2 Protection from solid objects up to
12 millimeters
3 Protection from solid objects more
than 2.5 millimeters
4 Protection from solid objects more
than 1 millimeter
5 Protected from dust, limited ingress
6 Totally protected from dust, dust tight
—
—
Second IP Number
0 No protection
1 Protection from vertically falling
drops of water and condensation
2 Protection from direct sprays of
water up to 15° from the vertical
3 Protection from direct sprays of
water up to 60° from the vertical
4 Protection from splashing water
from all directions
5 Protection from low-pressure
water jets from all directions
6 Protection from high-pressure
water jets
7 Protection from temporary immersion
up to 1 meter
8 Protection from long periods
of immersion under pressure
Third IP Number
0 No protection
1 Protection from impact of 0.225 joules
(150 grams falling from 15 cm)
(1.5 kilograms falling from 40 cm)
6 Protection from impact of 20 joules
(5 kilograms falling from 40 cm)
—
—
31
Other Standards
Ethernet/Industrial Protocol.
The Ethernet/Industrial Protocol (Ethernet/IP) standard, usually
called Industrial Ethernet, is an open standard. Industrial Ethernet
adapts ordinary, off-the-shelf IEEE 802.3 Ethernet physical media
to industrial applications. In addition, all the TIA/EIA 568-B.1,
568-B.2, and 568-B.3 standards apply in harsh environments.
TIA/EIA 1005: Industrial Telecommunication
Infrastructure.
The TIA TR-42.9 subcommittee is developing the TIA/EIA 1005
standard to address harsh environments. It defines the requirements
for cabling, connectors, pathways, and spaces and will establish
four environmental conditions with the acronym MICE:
• Mechanical (shock, vibration, impact, etc.)
• Ingress (contamination influx)
• Climate (temperature, humidity, UV exposure, etc.)
• Electromagnetic (conducted and radiated interference)
Ingress Protection.
The Ingress Protection (IP) ratings, developed by the European
Committee for Electrotechnical Standardization (CENELEC), specify
the environmental protection equipment enclosures provide.
It consists of two or three numbers: The first number refers to
protection from solid objects or materials; the second number refers
Industrial environments
to protection from liquids; and the third number, commonly omitted,
refers to protection against mechanical impacts. For example, an
IP67-rated connector is totally protected from dust and from the
effects of immersion in 5.9 inches (15 cm) to 3.2 feet (1 m) of water
for 30 minutes. Because office-grade RJ-45 connectors do not stand
up in industrial environments, the Ethernet/IP standard calls for
sealed industrial RJ-45 connectors that meet an IP67 standard.
NEMA ratings.
The National Electrical Manufacturers’ Association (NEMA) issues
guidelines and ratings for an enclosure’s level of protection against
contaminants. Here are a few of the most common ratings:
NEMA 3 and 3R enclosures, for indoor and outdoor use, protect
against falling dirt, windblown dust, rain, sleet, snow, and ice
formation. NEMA 3R is identical to NEMA 3 except that it doesn’t
specify protection against windblown dust.
NEMA 4 and 4X enclosures, for indoor and outdoor use, protect
against windblown dust and rain, splashing and hose-directed
water, and ice formation. NEMA 4X goes further, specifying
protection against corrosion caused by the elements.
NEMA 12 enclosures, for indoor use, protect against falling dirt;
circulating dust, lint, and fibers; dripping or splashing non-corrosive
liquids; and oil and coolant seepage.
Ingress Protection Ratings

Horizontal cabling
Backbone cabling
Horizontal cabling
Horizontal Distribution Area
(LAN/SAN/KVM switches)
Zone Distribution Area
Equipment Distribution Area
(Cabinets/Racks)
Offices, Operations Center,
Support Rooms Access providers
Telecommunications Room
(Office and operations
center LAN switches)
Horizontal cabling
Horizontal cabling
Section Name
Section Name
Other Standards
The data center is the building, or portion of a building, that houses computer rooms and support facilities.
Traditionally, there were no design guidelines for data centers. That changed in 2005 with the ratification of
TIA/EIA-942: Telecommunications Infrastructure Standards for Data Centers, which was developed to ensure
uniformity in design and performance. It was created for data center designers who are early in the
building development process. A good part of the standard involves facility specifications, functional
areas, and equipment placement in a hierarchical star topology. The standard includes:
Data center spaces.
When planning a data center, plan plenty of ”white space”
or empty space to accommodate future equipment. The basic
elements of the data center include:
Entrance Room(s). It’s recommended that this be outside
of the computer room for security.
Main Distribution Area (MDA). This is in a centrally located
area to house the routers and switches. It includes the main
cross-connect (MC), and may include a horizontal cross-connect.
Horizontal Distribution Areas (HDA). There may be one or
more HDAs, which serve as the distribution point for horizontal
cabling. The HDA houses the horizontal cross-connects and active
equipment, such as switches.
Equipment Distribution Areas (EDA). These are where the
horizontal cables are terminated in patch panels. See ”hot and
cold aisles” on the facing page.
Zone Distribution Area (ZDA). This is an optional interconnection
or consolidation point between the EDA and HDA for zone cabling.
Backbone and Horizontal Cabling.
Equipment Distribution Area Outlet.
• Architecture
• Cabling infrastructure
• Pathways and spaces
• Redundancy
• Network design
• Topology
• Racks and cabinets
• Access
• Power
• Environmental design
• Fire protection
• Water intrusion
• Security
• Disaster avoidance/recovery
• Best practices
Data center infrastructure
(Cabinets/Racks)
Backbone cabling

Access providers
Primary Entrance Room
(Carrier equipment and demarcation)
Backbone cabling
(Cabinets/Racks)
33
Other Standards
Recommended media.
Like the TIA/EIA-568-B standards, the TIA-942 recommends:
• 100-ohm twisted pair cable, Category 6. (At the time of this
writing, Augmented Category 6 is still in draft form.)
• 50- and 62.5-micron multimode fiber optic cable.
Laser-optimized 50-micron is recommended.
• Single-mode fiber optic cable
• 75-ohm coax cable
Each cable type is still governed by all the applicable
requirements in TIA/EIA-568-B.2 and TIA/EIA-568-B.3.
Data center pathways.
The standard lists many recommendations for cable
management, such as each cable type must have separate racks
and pathways. Power cables must be in separate pathways with a
physical barrier. Abandoned cable should be removed. And large
data centers should have access floor systems for running cable.
Hot and Cold Aisles. Cabinets and racks should be arranged in
rows of alternating patterns with the fronts facing each other to
create “hot and cold” aisles. Cold aisles are in front of the cabinets
and racks. Hot aisles are behind the cabinets and racks where
the hot equipment air is exhausted. In addition, there should a
minimum of 1 meter (3.3 ft.) of front space provided for equipment
installation. A front clearance of 1.2 meters (3.9 ft.) is preferred.
A minimum space of 0.6 meters (2 ft.) is required for the rear
clearance with 1 meter (3.3 ft.) preferred. For easy under-floor cable
access, the cabinets and racks should be aligned with the floor tiles.
Redundancy.
Crucial to the operation of any data center are fail-safe systems
that enable continued operation despite catastrophic conditions.
The standard includes four tiers of data center availability. The tiers
are based on research from the Uptime Institute.
Tier 1: Basic
• 99.671% availability
• Annual downtime: 28.8 hours
• Single path for power and cooling
• No redundant components
Tier 2: Redundant Components
• Annual downtime: 22 hours
• Single path for power and cooling
• Redundant components (N + 1)
Tier 3: Concurrently Maintainable
• Multiple power and cooling paths
• Redundant components (N + 1)
Tier 4: Fault Tolerant
• Multiple power and cooling paths
• Redundant components 2 (N + 1)
NOTE: N indicates need or level of redundant components for
each tier with N representing only the necessary system need.
(Cabinets/Racks)
Main Distribution Area
(Routers, backbone, LAN/SAN switches,
PBX, M13 muxes)
Backbone cabling
Backbone cabling
Horizontal cabling Horizontal cabling
Secondary Entrance Room
(Carrier equipment and
demarcation)
Back
Back
Front
Front
Front
Hot aisle
Cold aisle
Cable trays
Cable trays
Power cable

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