Structured Cabling Supplement

Sponsored by:



Structured Cabling
Supplement

Cisco Networking Academy Program
CCNA 1: Networking Basics v3.0




Objectives
The Structured Cabling supplement for CCNA curriculum provides
curriculum and laboratory exercises in the following areas:
STRUCTURED CABLING SYSTEMS
STRUCTURED CABLING STANDARDS AND CODES
SAFETY
TOOLS OF THE TRADE
INSTALLATION PROCESS
FINISH PHASE
THE CABLING BUSINESS
Completing this material and the associated labs will provide a broad
introduction to all facets of structured cabling installation.
Structured cabling systems provide insight into the rules and
subsystems of structured cabling for a localarea network (LAN). A
LAN is defined as a single building or group of buildings in a campus
environment in close proximity to one another, typically less than two
square kilometers or one square mile. Structured cabling
systematically connects all parts of the LAN starting at the

demarcation point, working through the various equipment and
telecommunications rooms, and continuing to the work area. The
issue of scalability is also addressed. The learning objectives for
Structured Cabling Systems follow:
1.1 Rules of structured cabling for LANs
1.2 Subsystems of structured cabling
1.3 Scalability
1.4 Demarcation Point
1.5 Telecommunications and Equipment Rooms
1.6 Work areas
1.7 MC, IC, and HC

Structured Cabling Standards And Codes introduces the standards
setting bodies that put forth the guidelines that cabling specialists
work by. Important information about these international standards
organizations is introduced.
The learning objectives for Structured Cabling Systems follow:
2.1 Telecommunications Industry Association (TIA) and Electronic
Industries Association (EIA)
1-2 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

2.2 European Committee for Electrotechnical Standardization
(CENELEC)
2.3 International Organization for Standardization (ISO)
2.4 U.S. Codes
2.5 Evolution of Standards

Safety is an important chapter containing information often
overlooked in coverage of low voltage telecommunications wiring.
Students not accustomed to working in the physical workplace will

benefit from the labs and training in this section.
The learning objectives for Safety follow:
3.1 Safety Codes and Standards for the United States
3.2 Safety Around Electricity
3.3 Lab and Workplace Safety Practices
3.4 Personal Safety Equipment

Tools Of The Trade, as with any craft, are often what makes the
difference between a hard job with mediocre results and a simple job
with outstanding results. This module gives the students hands-on
experience with several of the tools used by telecommunications
cabling installers to have professional results.
The learning objectives for Tools of the Trade follow:
4.1 Stripping and Cutting Tools
4.2 Termination Tools
4.3 Diagnostic Tools
4.4 Installation Support Tools

Installation Process contains the elements of an installation, starting
from the rough- in phase where the cables are pulled into place. Riser
(backbone) cables are discussed, as are the fire stops used where a
cable passes through a fire rated wall. Copper terminations are
covered, as are wall adapters and other fixtures.
The learning objectives for Installation Process follow:
5.1 Rough-In Phase
5.2 Vertical Backbone and Horizontal Cable Installation
5.3 Fire-stops
5.4 Terminating Copper Media
1-3 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

5.5 The Trim Out Phase

Finish Phase is the point at which installers test and in some cases
certify their work. Testing assures that all cables are properly routed
to their appointed destination. Certification is a statement of the
quality of the wiring connection certifying that it meets the
requirements defined by the Industry Standards.
The learning objectives for Finish Phase follow:
6.1 Cable Testing
6.2 Time domain reflectometer (TDR)
6.3 Cable Certification and Documentation
6.4 Cutting over

The Cabling Business requires its share of attention, as does the
business side of any other enterprise. Before cables can be installed,
there must be a bid. Before there can be a bid there must be a request
for a proposal, and walk-throughs to determine the precise scope of
the work. Documentation both to describe the project and to show
how it was actually built may be required. Licenses may be required
to perform the work, and perhaps union membership. All projects
must be performed in a timely manner, with minimal waste of time or
materials. This is usually a job for project planning and using
program management applications.

The learning objectives for Cabling Business follow:
7.1 Site Survey
7.2 Labor Situations
7.3 Contract Revision and Signing
7.4 Project Planning
7.5 Final Documentation

Lab exercises give the student the opportunity to practice the manual
skills portion of structured cabling installation. The Case Study is
designed to give the student a hands-on opportunity to participate in
the design of a structured cabling system for a fictitious software
development company that is occupying a new three-story building
and requires it to be built out.
1-4 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1 Structured Cabling Systems
1.1 Rules of structured cabling
Structured cabling is a systematic approach to cabling. It is a method
for creating an organized cabling system that can be easily
understood by installers, network administrators, and any other
technicians that deal with cables.
The following three rules will help ensure that the structured cabling
design projects are both effective and efficient:
Look for a complete connectivity solution - An optimal solution for
network connectivity includes all the systems that are designed to
connect, route, manage, and identify structured cabling systems. A
standards-based implementation will help to make sure that both
current and future technologies can be supported. Following
standards will make sure that the project will deliver performance and
reliability over the long term.
Plan for future growth – The number of cables installed should meet
these future requirements as well. Category 5e, Category 6, and fiber-
optic solutions should be considered where feasible to ensure that
future needs will be met. It should be possible to plan a physical layer
installation that works for ten or more years.
Maintain freedom of choice in vendors - A non-standard compliant

system from a single vendor may make it more difficult to make any
moves, adds, and changes to the cabling infrastructure at a later time.
Even though a closed and proprietary system may be less expensive
initially, this could end up being much more costly over the long term

Web Link:
/>arkets/Finance/rules.asp
1-5 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1.2 Subsystems of structured cabling

Figure 1 Subsystems of Structured Cabling
There are seven subsystems associated with the structured cabling
system (See Figure 1). Each subsystem performs certain functions to
provide voice and data services throughout the cable plant.
■
Demarcation point (demarc) within the entrance facility (EF) in
the equipment room
■
Equipment Room (ER)
■
Telecommunications room (TR)
■
Backbone cabling - also known as vertical cabling
■
Distribution cabling - also known as horizontal cabling
■
Work area (WA)
■
Administration

The demarc is where outside service provider cables interface with
the customer’s cables in the facility. Backbone cabling is the the
feeder cables that are routed from the demarc to the Equipment
Rooms and then on to the Telecommunications Rooms throughout the
facility. Horizontal cabling distributes cables from the
Telecommunication Rooms to the work areas. The
telecommunications rooms are where connections take place to
provide a transition between the backbone cabling and horizontal
cabling.
These subsystems make structured cabling, by nature, a distributed
architecture with management capabilities that are limited to the
active equipment (PCs, switches, hubs, etc.) Designing a structured
1-6 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

cabling infrastructure that properly routes, protects, identifies and
terminates the copper or fiber media is absolutely critical for network
performance and future upgrades.

1-7 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1.3 Scalability
A LAN that can accommodate future growth in size is referred to as
being scalable. It is very important to plan ahead when estimating the
number of cable runs and cable drops in a work area. It is always
easier to ignore extra installed cables than to not have them when
they are required.
In addition to pulling extra cables in the backbone area for future
growth, it is also common practice to pull an extra cable to each
workstation or desktop for future use. This gives protection against
pairs that may fail on voice cables during installation, and it also

provides for expansion. It is also a good idea to provide a pull string
when installing the cables to make it easier for adding cables in the
future. Whenever new cables are added, a new pull string should also
be added.
1.3.1 Backbone Scalability
To determine how much extra copper cabling to pull, first determine
the number of runs that are needed now, and add some extra, say
about 20%.
Another way to obtain this reserve capability is to use fiber-optic
cabling and equipment in the building backbone. Updating the
termination equipment (by inserting faster lasers and drivers, for
example) can accommodate fiber growth.
1.3.2 Work Area Scalability

Figure 1 Allow for Growth
While it may be obvious that each work area needs one cable for
voice and one for data, there are other devices that may need a
connection to either the voice or data system. Network printers, FAX
1-8 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

machines, laptops, or another user in the work area can all require
their own network cable drops.
Once the cables are in place, use multi-port wall plates over the jacks.
There are many types of configurations that are possible for either
modular furniture or partition walls . In addition, use jacks that are
color-coded to make it easier to identify types of circuits.
Administration standards require that every circuit is clearly labeled
to assist in connections and troubleshooting.
A new technology that is becoming very popular is Voice over
Internet Protocol (VoIP). This technology allows special telephones

to use data networks when placing telephone calls. A great advantage
to this technology is the ability to avoid costly long distance charges
by using this service over existing data network connections. Other
devices like a printer or computer can be plugged into the IP phone..
Even if these types of connections are planned, enough cables should
be installed to allow for growth. Especially considering that the
growth will include integrated IP video traffic as well in the not too
distant future.
To accommodate the changing needs of users in offices, it is
recommended to provide at least one additional spare cable to the
work area outlet.. Offices may change from single user to multi-user
spaces. In these cases, a work area can become inefficient if only one
set of communication cables were pulled. Assume that every work
area could accommodate multiple users in the future (See Figure 1).
Traditionally, business networks were built to support delivering
services such as telephone, data, video, surveillance, etc. Each service
required a different infrastructure consisting of hardware, software
and media to deliver and manage the service. A trend in today’s
network infrastructure centers on the convergence of voice, data and
video traffic over one network infrastructure. This profound change
creates a network cabling infrastructure that is even more important
to your business.

1-9 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1.4 Demarcation Point
Figure 1 Demarcation Point
The demarcation point (demarc), provides the point at which outdoor
Service Provider cabling interfaces with the intra-building backbone
cabling (See Figure 1). It represents the boundary between the service

provider's responsibility and that of the customer. In many buildings,
this location is the same point of presence (POP) for other utilities
such as electricity and water.
The service provider is responsible for everything from the demarc
out to the service provider's facility. Everything from the demarc into
the building is the customer's responsibility.
The local telephone carrier is typically required to terminate cabling
within 15 m (49.2 ft) of building penetration and to provide primary
voltage protection. This is usually installed and provided by the
service provider.
The Telecommunications Industry Association (TIA) and Electronic
Industries Association (EIA) develop and publish standards for many
industries including the cabling industry. To ensure that the cabling
installation is safe, installed correctly, and retains performance
ratings, these standards should always be followed when performing
any voice or data cabling installation or maintenance.
The TIA/EIA-569-A standard specifies the requirements for the
demarc space. The standards for the structure and size of the demarc
space are based on the size of the building. In buildings that are larger
1-10 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

than 2000 usable square meters, a locked, dedicated, and enclosed
room is recommended.
The following are general guidelines when setting up a demarcation
point space:

■
Allow one square meter (10.7 ft²) of plywood wall mount for
each 20 square meter (215.3 ft²) area of floor space.
■

The surfaces where the distribution hardware is mounted must be
covered with fire-rated plywood or plywood that is painted with
two coats of fire retardant paint.
■
Either the plywood or the covers for the termination equipment
should be colored orange to indicate the Point of Demarcation.

1.5 Telecommunications and Equipment Rooms

Figure 1 Telecommunications Room
1-11 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.


Figure 2 Panduit Distribution Rack
After the cable enters the building through the demarc, it travels to
the Entrance Facility (EF), which is usually in the Equipment Room
(ER). The equipment room is the center of the voice and data
network. An equipment room is essentially a large
telecommunications room that may house the main distribution
frame, network servers, routers, switches, the telephone PBX,
secondary voltage protection, satellite receivers, modulators, high
speed Internet equipment, and so on. The design aspects of the
equipment room are specified in the TIA/EIA-569-A standard.
In larger facilities the equipment room it may feed one or more
Telecommunications Rooms (TR) which are distributed throughout
the building. A Telecommunications Room, is an area within a
building that houses the telecommunications cabling system
equipment (See Figure 1) for a particular area of the LAN such as a
floor or part of a floor. This includes the mechanical terminations
and/or cross-connect devices for the horizontal and backbone cabling

system. It would also be common for departmental or workgroup
switches, hubs, and possibly routers to be located in the TR..

A wiring hub and patch panel in a TR may be mounted to a wall with
a hinged wall bracket, a distribution rack (See Figure 2), or a full
equipment cabinet.
If the choice is a hinged wall bracket, the bracket must be attached to
the plywood panel that covers the underlying wall surface. The
purpose of the hinge is to allow the assembly to swing out so that
technicians can easily access the backside of the wall. Care must be
taken, however, to allow 48 cm (18.9 in) for the panel to swing out
from the wall.
If using a distribution rack, then there must be a minimum of 1 meter
(3 feet) of workspace clearance in the front and rear of the rack. A
1-12 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

55.9 cm (22 in) floor plate, used to mount the distribution rack, will
provide stability, and will determine the minimum distance for its
final position.
If the patch panel, hub and other equipment are mounted in a full
equipment cabinet, they require at least 76.2 cm (28.6 in) of clearance
in front, in order for the door to swing open. Typically, such
equipment cabinets are 1.8 m high x .74 m wide x .66 m deep (5.9 ft
x 2.4 ft x 216.5 ft).
Equipment must be placed into equipment racks with care.
Considerations include whether or not the equipment uses electricity,
cable routing, cable management, and ease of use. For example, a
patch panel would not be placed high on a rack if a significant
number of changes were to take place after the systems were
installed. Convenience of use is a large consideration when planning

the equipment layout. Heavier equipment such as switches and
servers should be placed near the bottom of the rack for stability.
Scalability is also a consideration in an equipment layout, as future
growth should be accommodated. Space should be left on a rack for
future patch panels, or floor space left for future rack installations in
an initial layout.
Proper installation of equipment racks and patch panels in the TR will
allow easy changes and modifications to the cabling installation in the
future. This is important when considering the design and layout of
the work areas.

1.6 Work areas

Figure 1 Work Areas
1-13 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

The area serviced by an individual telecommunications room is
usually one floor or part of a floor in a building (See Figure 1). The
size of the TR is dependent upon the size of the area being served.
One TR can accommodate up to 1000 square meters (10,000 sq. ft). If
the area to be served exceeds that, then another TR needs to be
provided for that floor or area. The floor space served by the TR is
divided into individual work areas. This is where the occupants of the
building will normally work and interact with their
telecommunications equipment such as telephones, computers,
printers, fax machines, etc. A work area is typically 10 square meters
(100 sq. ft.)
The maximum distance for a cable from the termination point in the
TR to the termination at the Work Area outlet must not exceed 90
meters (295 ft.). This 90 meter maximum horizontal cabling distance

is referred to as the Permanent Link. Each work area must have at
least two cables, one for data and the other for voice. As previously
discussed, accommodations for other services and future expansion
must also be considered.
Cables cannot usually be strung across the floor, but rather usually
ride in wiring management devices such as trays, baskets, ladders,
and raceways. These devices route the paths of the cables above
workspaces, often in the plenum areas above suspended ceilings. This
means that the height of the ceiling times two (once up to the wiring
management device, once back down) must be subtracted from the
proposed work area radius.
In addition, ANSI/TIA/EIA-568-B specifies that there can be 5
meters (16.4 ft) of patch cord to interconnect equipment patch panels,
and 5 meters of cable from the cable termination point on the wall to
the telephone or computer. This additional maximum of 10 meters of
patch cordage added to the Permanent Link is referred to as the
Horizontal Channel. The maximum distance for a Channel is 100
meters, the 90 meter maximum Permanent Link plus 10 meters
maximum of patch cords.

1-14 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1.6.1 Servicing the Work Area

Figure 1 Servicing the Work Areas
Patching is done when connectivity changes are needed often or are
foreseen. It is much easier to simply patch the cable from the work
area outlet circuit to a different location in the TR than it would be to
remove terminated wires from connected hardware and re-terminate
them to another circuit. Patch cords are also used to connect

networking equipment to the cross-connects in a TR. Patch cords are
limited by the TIA/EIA-568-B.1 standard to five meters
A uniform wiring scheme must be used throughout a patch panel
system. All jacks and patch panels should be wired using the same
wiring plan. If the T568A wiring plan is used for the information
outlets or jacks, T568A patch panels should be used. The same is true
for the T568B wiring plan.
Patch panels can be for UTP (Unshielded Twisted Pair), STP
(Shielded Twisted Pair), or used in enclosures for fiber-optic
connections. The most common patch panels are for UTP. These
patch panels use RJ-45 jacks. Patch cords with RJ-45 plugs connect
to these ports.
There is still a fault with this plan, however. There is no provision to
keep authorized maintenance personnel from installing unauthorized
patches or installing an unauthorized hub into a circuit.
There is an emerging family of automated patch panels, however,
which can provide extensive network monitoring in addition to
simplifying the provisioning of moves, adds, and changes. These
patch panels normally provide an indicator lamp over any patch cord
that need to be removed, and then once the cord is released, provide a
second light over the jack to which they should be re-affixed. In this
way the system can automatically guide a relatively unskilled
employee through moves adds and changes. In Figure [1], the Panduit
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PanView management system automatically flags operators to the
location of jacks that need to be repatched.
The same mechanism that detects when the operator has moved a
given jack works also to detect when a jack has been pulled. Thus, an
unauthorized resetting of a patch can trigger an event in the system

log, and if need be trigger an alarm. For instance, if a half-dozen
wires to the work area suddenly show up as being open, and it is 2:30
in the morning, likely this is an event worth looking into, as theft may
be occurring.
This is actually a Physical Layer implementation of enterprise
monitoring software. For years, systems using SNMP and RMON
packets have offered the ability to detect the conditions of network
computers from a central monitoring site. For instance, if the number
of hard disk clusters marked as bad is creeping upward at an
increasing rate, then it is likely that a hard disk failure may be
imminent. Network monitoring software can detect this condition and
summon a service person to attend the failing machine before the
failure occurs. This makes it much easier to back up and restore the
system, minimizing down time and preventing data loss.
1.6.2 Types of patch cables

Figure 1 UTP Patch Cable
Patch cables (See Figure 1) come in a variety of wiring schemes. The
most common, the straight through, has the same wiring scheme on
both ends of the cable. In other words, pin 1 on one end is connected
to pin 1 on the other end. Pin 2 on one end corresponds to pin 2 on
the other, and so on. These types of cables are used to connect PCs to
a network hub or switch.
When connecting a communications device, such as a router, switch,
or server, to a network hub or another switch, a crossover cable is
usually used. Crossover cables use the T568A wiring plan on one end
and T568B on the other.

1-16 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

Lab 1: Examination of Termination Types
1.6.3 Cable management

Figure 1 Panduit Rack-Mounted Vertical and Horizontal Cable
Management System
Cable management devices are used for routing cables and providing
a neat and orderly path for the cables and to assure minimum bend
radius is maintained. Cable management also eases cable additions
and modification to the wiring system. There are many options for
cable management in the TR. Cable baskets can be used when an
easy, lightweight installation is needed. Ladder racks are often used
when heavy loads of bundled cable need to be supported. Different
types of conduits can be used to run cable inside walls, ceilings,
floors, or when they need to be shielded from external conditions.
Cable management systems are used vertically and horizontally on
telecommunications racks to distribute cable in a neat and orderly
fashion (See Figure 1).
1-17 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

1.7 MC, IC, and HC

Figure 1 MC, HC, and IC Planning
Most networks have more than one TR for various reasons. First of
all, a medium or large network is usually spread over many floors or
buildings in campus environmemts. A minimum of one TR is needed
for each floor of each building (See Figure 1).
Secondly, media can only carry a signal so far before the signal starts
to degrade or attenuate. Therefore, TRs are located at defined
distances throughout the LAN to provide interconnects and cross-
connects to hubs and switches to assure desired network performance.

At these points, equipment such as repeaters, hubs, bridges, or
switches are needed to regenerate the signal and then send it on. This
equipment is stored in some type of TR whether it is a small room or
even just a cabinet.
Not all TRs are equal. The primary TR, called the main cross-connect
(MC), is the center of the network. This is where all the wiring
originates and where most of the equipment is housed. The
intermediate cross-connect (IC) is connected to the MC and may
house the equipment for a building on a campus. The horizontal
cross-connect (HC) provides the cross-connect between the backbone
and horizontal cables on a single floor of a building.
1.7.1 Main cross-connect (MC)
The MC is the main concentration point of an entire building or
campus. The MC is in effect the primary TR. It is the room that
controls the rest of the TRs (the ICs and HCs) in a building or
campus. In some networks, it is the place where the inside cable plant
meets the outside world's connectivity (the demarc).
1-18 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

All ICs or HCs are connected to the MC in a star topology. Backbone,
or vertical cabling is used to connect those ICs and HCs located on
other floors. Where the entire network is confined to a single multi-
story building, the MC is usually located on one of the middle floors
of the building, even though the demarc might be located in an
entrance facility on the first floor or in the basement.
For campus networks that comprise multiple buildings, one building
typically houses the MC and each individual building typically has its
own version of the MC called the intermediate cross connect (IC) that
connects all the HCs within the building. The IC allows the extension
of backbone cabling from the MC to each HC..

There may only be one MC for the entire structured cabling
installation. The MC feeds the ICs, and each IC feeds multiple HCs.
There can be only one IC between the MC and any HC.
The backbone cabling (red lines in the figure) runs from the MC to
each of the ICs. The ICs are located in each of the campus buildings,
and the HCs serve work areas. Horizontal cabling, running from the
HCs to the work areas, is represented by the black lines.
1.7.3 Backbone cabling
Any cabling installed between the MC and another TR is known as
backbone cabling. The difference between horizontal and backbone
cabling is clearly defined in the standards. Backbone, or vertical,
cabling consists of the backbone cables, intermediate and main cross-
connects, mechanical terminations, and patch cords or jumpers used
for backbone-to-backbone cross-connection. Backbone cabling
includes:
■
TRs on the same floor (MC to IC, IC to HC)
■
Vertical connection (risers) between TRs on different floors (MC
to IC)
■
Cables between TR and demarcation point
■
Cables between buildings (inter-building) in a multi-building
campus
The maximum distances for cabling runs vary from one type of cable
to another. For backbone cabling, the maximum distance for cabling
runs can also be affected by how the backbone cabling is to be used.
To understand what this means, assume that a decision has been made
to use single-mode fiber-optic cable for the backbone cabling. If the

networking media were to be used to connect the HC to the MC, then
the maximum distance for the backbone cabling run would be 3000 m
(9,842.5 ft).
At times the maximum distance of 3000 m (9,842.5 ft) for the
backbone-cabling run must be split between two sections, as when the
backbone cabling is to be used to connect the HC to an IC and the IC
to the MC. When this occurs, the maximum distance for the backbone
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cabling run between the HC and the IC is 300 m (984 ft). The
maximum distance for the backbone cabling run between the IC and
the MC is 2,700 m (8855 ft).
1.7.4 Fiber-Optic Backbone
Fiber optics are an extremely effective means of moving backbone
traffic. Fiber optic cable is capable of carrying more data at higher
speeds over greater distances than copper. Optical fibers are also
impervious to electrical noise and radio frequency interference. Fiber
also does not conduct electrical currents that can cause ground loops,
it transmits pulses of light. Fiber optic systems also have high
bandwidth and can work at high speeds. This means that a fiber optic
backbone with certain characteristics that is installed today may be
upgraded in the future to even greater performance, when the terminal
equipment is developed and becomes available. This can make fiber
optic very cost effective.
Fiber has an additional advantage when used as a backbone media. It
can go much farther than copper. Multimode optical fiber used as a
backbone can support lengths of up to 2000 meters. Single mode fiber
optic cables can go up to 3000 meters. Although optical fiber,
especially single mode fiber, can carry signals much farther than this
(60 – 70 miles is feasible, depending on terminal equipment), these

longer distances are considered to be out of the scope of the LAN
standards.d.

1.7.2 Horizontal cross-connect (HC)

Figure 1 Horizontal Cabling and Symbols
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The horizontal cross-connect (HC) is located in the TR closest to the
work areas. The HC, like all copper cross-connects, is typically a
patch panel or punch down block and possibly networking devices
such as hubs or switches. It can be a rack mounted in a room or in a
cabinet. Since a typical horizontal cable system includes multiple
cable runs to each workstation, it usually represents the largest
concentration of cable in the building infrastructure. A building with
a 1000 workstation LAN can typically contain a horizontal cable
system consisting of 2000 to 3000 individual cable runs.
Horizontal cabling includes the networking media, copper or optical
fiber, that is used in the area that extends from the wiring closet to a
workstation (See Figure 1). Horizontal cabling includes the
networking medium that runs along a horizontal pathway to the
telecommunications outlet or connector in the work area and the
patch cords or jumpers in the HC.
Any cabling installed between the MC and another TR is known as
backbone cabling. The difference between horizontal and backbone
cabling is clearly defined in the standards.

Lab 2: Terminating A Cat5e Cable at a Cat5e Patch Panel

1.7.5 MUTOAs and Consolidation Points

Figure 1 Typical MUTOA Installation
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Figure 2 Typical Consolidation Point Installation
Consolidation Points (CPs) and Multi-user Telecommunications
Outlet Assemblies (MUTOAs) are provided in the TIA 568 B.1
standard to accommodate open office areas. An open office area is a
modular furniture (cubicles) arrangement. These are often subject to
frequently being rearranged. Rather than replacing the entire
horizontal cabling system feeding these areas, a CP or MUTOA can
be located close to the open office area and eliminate the need to
replace the cabling all the way back to the TR whenever the furniture
is rearranged. The cabling only needs to be replaced between the new
work area outlets and the CP or MUTOA. The longer distance of
cabling back to the TR remains permanent.
A MUTOA is a device that allows users to move, add devices, and
make changes in modular furniture settings without re-running the
cable. Patch cords can be routed directly from a MUTOA to work
area equipment (See Figure 1). A MUTOA location must be
accessible and permanent, and may not be mounted in ceiling spaces
or under access flooring. Similarly, it cannot be mounted in furniture
unless that furniture is permanently secured to the building structure.
When using MUTOAs, the TIA/EIA-568-B.1 standard specifies the
following:
■
At least one MUTOA is needed for each furniture cluster.
■
Maximum 12 work areas can be used for each MUTOA.

■
Patch cords at work areas shall be labeled on both ends with
unique identifiers.
■
Maximum patch cord length is 22 m (72.2 ft).

Consolidation points (CP) provide limited area connection access.
Typically a permanent flush wall-mounted, ceiling-mounted, or
support column-mounted panel serves modular furniture work areas.
The panels must be unobstructed and fully accessible without moving
1-22 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

fixtures, equipment, or heavy furniture. Consolidation points differ
from MUTOAs in that workstations and other work area equipment
do not plug into the CP like they do with the MUTOA (See Figure 2).
Workstations plug into an outlet which is then hard wired to the CP.
The TIA/EIA-569 standard specifies the following:
■
At least one CP for each furniture cluster
■
Maximum 12 work areas for each CP
■
Maximum patch cord length is 5 m (16.4 ft)
For both consolidation points and MUTOAs, TIA/EIA 568-B.1
recommends a seperation of at least 15 m (49 ft.)equipment between
the TR and the CP or MUTOa. This is to avoid problems dealing with
crosstalk and return loss.
1-23 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.

2 Structured Cabling Standards and

Codes
Standards are sets of rules or procedures that are either widely used,
or officially specified, and that serve as the gauge or model of
excellence. Standards can take many forms. They can be specified by
a single vendor or be industry standards that support multi-vendor
interoperability:
■
Standardized media and layout descriptions for both backbone
and horizontal cabling.
■
Standard connection interfaces for the physical connection of
equipment.
■
Consistent and uniform design that follows a system plan and
basic design principles.
Numerous companies, organizations, and even government bodies
regulate and specify the cables in use. In addition to these
organizations, local, state, county, and national government agencies
issue codes, specifications, and requirements.
The power of standards is this. The network that is built to standards
should work well, or interoperate, with other standard network
devices. The long term performance and investment value of many
network cabling systems has been severely diminished by installers
not knowing or following mandatory and voluntary standards.
It is important to understand that these standards are constantly being
reviewed and periodically updated to reflect new technologies and the
ever-increasing requirements of voice and data networks. Just as new
technologies are added to the standards, others are dropped or phased
out. In many cases a network may include technologies that are no
longer a part of the current standard or being eliminated. Typically,

this does not require an immediate changeover, but these older,
slower technologies are eventually replaced in favor of faster ones.
Standards are often developed by or at the direction of international
organizations that try to reach some form of universal standard.
Organizations such as TIA, IEEE, ISO, and IEC are all examples of
international standards bodies. These international standards
organizations are composed of members from many nations, each of
which has their own standards making process.
In many countries, the national codes become the model for
state/provincial agencies as well as municipalities and other
governmental units to incorporate into their laws and ordinances. The
enforcement then moves to the most local authority. Always check
with local authorities to determine what codes are enforced. Local
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codes for the most part take precedence over national codes, which
take precedence over international codes.

2.1 Telecommunications Industry Association (TIA)
and Electronic Industries Association (EIA)

Figure 1 TIA/EIA Standards for buildings

Figure 2 TIA/EIA Structured Cabling Standards
The Telecommunications Industry Association (TIA) and Electronic
Industries Alliance (EIA) are trade associations that jointly develop
and publish a series of standards covering areas of structured voice
and data wiring for LANs (See Figure 1).
1-25 CCNA 1: Networking Basics v3.0 – Structured Cabling Supplement Copyright  2003, Cisco Systems, Inc.