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The Cabling Business 959
As-built drawings are not created until all cables are placed, all jacks are installed, and
all cables are terminated. Drawing can begin while final testing is taking place, but
assurances must be made that no changes or additional work is done that is not reflected
accurately in the drawings.
Floor plans, furniture plans, or T drawings usually are used as the basis for as-built
drawings. The contractor is not required to redraw the building plans for the as-built
drawings. The contractor draws all cable runs, terminations, and outlets, and supplies
all labeling information as it was installed.
The punch list is the checklist that the customer provides the contractor with when the
contractor considers the project complete (see Figure A-53).
Figure A-53 Typical Punch List
The punch list is a list containing items that were not completed (missing outlets or
cable runs, for example), items that were completed unsatisfactorily (cables not fastened
to ladder racks or outlets that do not work, for example), or cleanup items (debris left
in corridor, for example) that the customer requires corrected before approval for final
payment. The punch list can take the form of the customer’s final acceptance of the
project. When the items on the punch list are completed to the customer’s satisfaction,
payment is expected.
Punch List
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960 Appendix A: Structured Cabling
Case Study: FARB Software Development, Ltd.:
Network Design and Implementation
Lab exercises give you the opportunity to practice the manual skills portion of structured
cabling installation. The case study is designed to give you 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.
Overview
To complete this case study, you should be able to


■ Gather information for the preinstallation process and lay plans for the
installation process
■ Create documentation as would be required for creating a real network
■ Comply with TIA, EIA, and electrical standards
Using this supplement, as well as having mastered the CCNA 3 curriculum, will prepare
you to complete many tasks related to real-world network creation. These objectives
are spelled out within this case study in a letter from Cheryl Farb, president of FARB
Software Development, Ltd., who, for this case study, is serving as the client company.
The following are some review items that will help you to focus on the case study.
General Design Process Framework
Network design is best done by following a framework. Determining where the wires
go requires knowledge of the structure of the networks. You will need to know where
the users are and what their applications are before you can begin to sketch out a
viable network. A Layer 1 LAN logical and physical topology must be developed. This
development includes the type of cable and the physical (wiring) topology that are
selected, as well as the physical placement of infrastructure connection points on the
network.
A Layer 2 segmentation plan must be overlaid on the previously created Layer 1 topology.
This layer plan includes devices added to the topology to improve its efficiency and
functionality. Examples of these devices might be switches and bridges. This layer also
includes the use of technologies such as microsegmentation, virtual LANs (VLANs),
and the Spanning Tree Protocol (STP), to add efficiency and reliability.
A Layer 3 hierarchical plan then is overlaid on both of the previous two layers. This
plan includes adding Layer 3 devices that will provide intranetwork and internetwork
functionality to the network, as well as creating a network address plan. Layer 3 is
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Case Study: FARB Software Development, Ltd.: Network Design and Implementation 961
where routing and firewalls are implemented, imposing a logical structure on the net-
work. They also can be used for segmentation of both collision and broadcast domains.
An extension of the Layer 3 plan might be considered a Layer 4 plan. This plan could

be laid over the first three; it moves strictly to software and controls access and avail-
ability of the network. It involves access lists and firewall configuration. Although a
complete network design keeps moving up the OSI model, it is beyond the focus of this
project.
This design focuses on Ethernet, IP, Layer 1, Layer 2, and Layer 3, which is the focus
of this curriculum. The design process logically flows up the layers of the OSI model.
That said, it is important to remind ourselves of one of the purposes of structured
cabling. The cabling system must be able to withstand change and growth over its life
of service. Odds are good that most companies will be in different quarters by the time
their structured cabling system is worn out. This means that care must be taken to not
follow the current network layout so closely that the cables are not good for any other
organization that may follow. An appropriate structured cabling system may be said to
fit the network today, but accommodate easily the network of tomorrow.
The most important—and, many times, the most neglected—part of network design
and operation is the documentation. The main focus of this project is the documentation
of the network design. Documentation for this project should include wiring maps,
addressing schemes, any brainstormed ideas, problem-solving matrices, and any other
notes made while making these determinations.
Predesign Process
Before a network can be designed, the data needed to design the network must be
gathered. For a network to be effective and serve the needs of its users, this data
should be gathered according to a systematic series of preplanned steps. These steps
provide a guide to completely discover the data needed to create the network.
The first step in the process is to gather information about the organization. This
information should include the following:
■ Organization history and current status
■ Projected growth
■ Operating policies and management procedures
■ Building diagrams (blueprints)
■ Existing network diagrams and documentation

■ Office systems and procedures
■ Viewpoints of the people who will be using the LAN
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962 Appendix A: Structured Cabling
In the information packet that follows this section, you will find communications from
the president outlining FARB Software Development, Ltd. This document exists at
FARB Software Development LTD.doc.
In this letter, Farb indicates her specific requirements for this project.
The second step is to make a detailed analysis and assessment of the current and pro-
jected requirements gathered in the first step. This step identifies and defines issues or
problems that need to be addressed (for example, a remote room in the building might
not have network access). It also provides information about future network expansion
needs, access, and security.
The third step is to identify the resources and constraints of the organization. Organi-
zation resources that can affect the implementation of a new LAN system fall into the
categories of hardware, software, and human resources. If this were a network expansion
or upgrade, existing computer hardware and software would have to be documented.
Identification and definition of those projected needs also must be done. The answers
to some of these questions also will help determine how much training will be required
and how many people will be needed to support the LAN. The questions asked should
include the following:
■ What are the financial resources of the organization?
■ How are these resources currently linked and shared?
■ How many people will be using the network?
■ What are the computer skill levels of the network users?
■ What are the attitudes toward computers and computer applications?
Following these steps, documenting the information in the framework of a formal
report will help estimate costs and develop a budget for the implementation of a LAN.
Design Methodology and Deliverables
With the material that has been presented to this point, a strong foundation and

understanding should have been developed for the concepts of a layered communica-
tions model. Using the OSI model as the framework, an understanding of the functions
and devices that support operations at those layers also should have been gained.
To perform this case study, material related to the physical design and installation of a
network must be learned. As was presented in previous material, rules and standards
govern how a network is designed and built. These rules and standards must be
learned before the actual case study can be performed.
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Case Study: FARB Software Development, Ltd.: Network Design and Implementation 963
Students completing this lesson should be able to
■ Develop a Layer 1 and 2 topology
■ Gather information for both the preprocess and the process
■ Create documentation during the course of the process
■ Comply with TIA, EIA, and electrical standards
Note that this aligns with Farb’s requests for her company’s project.
Standards Organizations
When designing and building networks, it is necessary to ensure compliance with all
applicable fire codes, building codes, and safety standards. Perhaps the most important
part of the network-design process is designing according to the EIA/TIA and ISO/IEC
industry standards. The focus in this curriculum is on the standards for networking
media that have been developed and issued by the following groups:
■ ISO—International Organization for Standardization (not an acronym—see
glossary)
■ IEEE—Institute of Electrical and Electronics Engineers
■ UL—Underwriters Laboratories
■ EIA—Electronic Industries Alliance
■ TIA—Telecommunications Industry Association
The latter two organizations jointly issue a list of standards called the TIA/EIA standards.
In addition to these organizations, local, state, county, and national government agencies
issue specifications and requirements that can impact the type of cabling that can be

used in a local-area network.
It is also important to understand that these standards are being reviewed constantly
and are updated periodically 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 might include
technologies that are no longer a part of the current standard or that are being elimi-
nated. Typically, this does not require an immediate changeover, but these older, slower
technologies eventually are replaced in favor of faster ones.
Standards Definitions
The primary standards that will affect layer design have been created by the TIA/EIA.
The Telecommunications Industry Association (TIA) and the Electronic Industries Alli-
ance (EIA) are trade associations that jointly develop and publish a series of standards
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964 Appendix A: Structured Cabling
covering structured voice and data wiring for LANs. These industry standards evolved
after the U.S. telephone industry deregulation in 1984, which transferred responsibility
for on-premises cabling to the building owner. Before that, AT&T used proprietary
cables and systems.
Both the TIA and the EIA are accredited by the American National Standards Institute
(ANSI, section 6.2.7) to develop voluntary industry standards for a wide variety of
telecommunications products. This means that many standards often are labeled ANSI/
TIA/EIA. The various committees and subcommittees of TIA/EIA develop standards
for fiber optics, user premises equipment, network equipment, wireless communications,
and satellite communications.
TIA/EIA 568-A is the Commercial Building Standard for Telecommunications Wiring.
The standard specifies minimum requirements for telecommunications cabling, recom-
mended topology and distance limits, media and connecting hardware performance
specifications, and connector and pin assignments. Several supplements cover some of
the newer, faster copper media. This standard has been replaced by TIA/EIA-568-B.
TIA/EIA-568-B is the Cabling Standard. This standard specifies the component and

transmission requirements for media. TIA/EIA-568-B.1 specifies a generic telecommu-
nications cabling system for commercial buildings that will support a multiproduct,
multivendor environment. TIA/EIA-568-B.1.1 is an addendum that applies to four-pair
unshielded twisted-pair (UTP) and four-pair screened twisted-pair (ScTP) patch cables’
bend radius. TIA/EIA-568-B.2 specifies cabling components, transmission, system mod-
els, and the measurement procedures needed for verification of twisted-pair cabling.
TIA/EIA-568-B.3 specifies the component and transmission requirements for an optical-
fiber cabling system.
TIA/EIA 569-A is the Commercial Building Standard for Telecommunications Pathways
and Spaces. The standard specifies design and construction practices within and between
buildings that are in support of telecommunications media and equipment. Specific
standards are given for rooms or areas and pathways into and through which telecom-
munications equipment and media are installed.
TIA/EIA-606 is the Administration Standard for the Telecommunications Infrastructure
of Commercial Buildings, including cable-labeling standards. The standard specifies
that each hardware-termination unit must have some kind of unique identifier. This
identifier must be marked on each termination hardware unit or on its label. When
identifiers are used at the work area, station terminations must have a label on the
faceplate, the housing, or the connector itself. All labels must meet legibility, deface-
ment, and adhesion requirements as specified in UL969.
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Case Study: FARB Software Development, Ltd.: Network Design and Implementation 965
TIA/EIA-607 is the standard for Commercial Building Grounding and Bonding Require-
ments for Telecommunications. It supports a multivendor, multiproduct environment,
as well as the grounding practices for various systems that might be installed on cus-
tomer premises. The standard specifies the exact interface points between the building
grounding systems and the telecommunications equipment grounding configuration,
and specifies building grounding configurations needed to support this equipment.
Electrical Safety
Generally, electrical current follows the path of least resistance. Because metals such as

copper provide little resistance, they frequently are used as conductors for electrical
current. Materials such as glass, rubber, and plastic provide more resistance and do not
make good electrical conductors. Instead, these materials frequently are used as insula-
tors. They are used to insulate conductors to prevent shock, fires, and short circuits.
Many different shapes of electrical outlets exist throughout the world. Two of the three
connection points provide the power circuit. The third connector protects people and
equipment from shocks and short circuits. This connector is called the safety ground
connection. In electrical equipment where this is used, the safety ground wire is connected
to any exposed metal part of the equipment. If there is a wiring fault inside of the device,
the ground connection protects people from exposure to hazardous voltages.
An accidental connection between the hot wire and the chassis is an example of a wiring
fault that could occur in a network device. If such a fault were to occur, the safety ground
wire connected to the device would serve as a low-resistance path to the earth ground.
The safety ground connection provides a lower resistance path than the human body,
thus reducing the risk of shock or electrocution.
When properly installed, the low-resistance path, provided by the safety ground wire,
offers sufficiently low resistance and current carrying capacity to prevent the buildup of
hazardously high voltages. The circuit links directly to the hot connection to the earth.
Telecommunications Room Requirements
Layer 1 design is the largest component of the total network design. It involves the
implementation of the preliminary designs gathered in the preprocess phase of the net-
work design to create the structured cabling system. This includes, but is not limited
to, creating the logical topology, creating the wiring map, selecting wiring closets, and
More Information
For more information on the various TIA/EIA standards codes, visit
www.rvcomp.com/wiring/EIA/organizations_codes.htm.
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966 Appendix A: Structured Cabling
selecting cable. This design must conform to the appropriate standards organization’s
rules for design.

Students completing this lesson should be able to:
■ List location and design requirements for telecommunications rooms
■ Explain cable-management design and specification
■ List considerations for selecting and installing equipment racks
■ Explain key environmental, safety, and power considerations in telecommunica-
tions room location, design, and installation
Work-Area Cabling
Work-area cabling extends from the telecommunications outlet in a room to the user
workstation. Work-area cabling is designed to be relatively simple to interconnect so
that it can be moved or changed relatively easily. Each work area serves a maximum of
10m
2
of usable floor space.
Work-area equipment includes the following components:
■ Workstation equipment, such as computers, data terminals, telephones, fax
machines, and printers
■ Cables, such as patch cables, modular cords, PC adapter cables, and fiber jumpers
■ Adapters external to the telecommunications outlet
The TIA/EIA-568-B standard requires a minimum of two telecommunication outlets
for each individual work area. The first outlet must be a four-pair, 100 Ω unshielded
twisted pair (UTP) or screened twisted pair (ScTP) cable and connector. Category 5e is
recommended for this outlet. The standard allows three choices for the second outlet:
■ Four-pair, 100 Ω UTP or ScTP cable and connector (Category 5e recommended)
■ Two-fiber 62.5/125 µm or 50/125 µm optical fiber and connector
■ 150 Ω shielded twisted-pair (STP) cable and connector (not recommended for
new installations)
Network Applications at FARB
Estimating the amount of traffic that the network will carry requires you to understand
the nature of the traffic. Database transfers seem to take a lot of bandwidth, as does
videoconferencing. Web applications are often gentle on bandwidth, with the excep-

tion of streaming audio and video applications.
The IT staff at FARB has an accumulated a list of software applications frequently used
by the staff. This is broken out by which group of users uses which application.
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Case Study: FARB Software Development, Ltd.: Network Design and Implementation 967
You can find the information about FARB and software requirement list in the Case
Study Materials section on the CD-ROM that accompanies this book.
Where Does It All Go?
FARB has not progressed in its planning to the point that you have been told which
users get what seats, nor even which department gets which area of the building. You
have been handed some fairly developed blueprints from which to begin your efforts.
They are entirely adequate for locating the telecommunications rooms in the project.
You can find these drawings for desk assignments, plumbing and HVAC, rooms, and
electric telephone and lighting, along with the building plan legend, roof cross-section
end view and side view, in the Case Study Materials section on the CD-ROM that
accompanies this book.
As is often the case, not all the information that you need is on any one drawing. Fur-
thermore, some of the drawings seem to be not useful to your requirements. Neverthe-
less, they are a good start toward designing a network to meet FARB’s requirements.
Note that there is no indication of where the TRs should go, with the exception of the
entrance facility, marked Point of Presence, on the ground floor. There is no indication
of which areas of the building are to be occupied by which department. Consult the
teacher or lab instructor of for this information.
The following section contains hints that should help students work out some of these
issues.
Structured Cabling Case Study Hints
This case study will give you experience in practicing your networking and cabling
skills. As you work through the study, you goal is to design the network layout for
FARB Software Development, Ltd. You will reach this goal by performing several
tasks involved in understanding the request for information and in deriving that infor-

mation from the drawings.
Four layers of documentation are involved:
1. A file that specifies President Cheryl Farb’s idea for the network facility in the
proposed new FARB building.
2. A requirements document that has been worked up by the internal IP staff, of
which you are a part. This lists what must be connected where.
3. Several sets of drawings of each of the four floors of the building.
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968 Appendix A: Structured Cabling
4. Some detail drawings to give you some idea of the methods of construction to
be used. This will help you make decisions about cable routing.
Take your time as you work through this case study. You will find that much of the
value will come from trying several different approaches. Discussion with class mem-
bers and teammates might help solidify your understanding of the important topics
that this case study brings forward.
Instructions:
Locate the letter to the internal support team from President Cheryl Farb. This docu-
ment shows ten items on which your ideas and input are requested. The last part of the
letter includes a forecast of the company growth.
Here are the ten items (some of them have several steps):
1. Recommendations of network equipment
2. Recommendations of network cabling
3. Any construction requirements
4. Network equipment locations
5. A wiring plan that includes the following:
— A horizontal and vertical logical layout
— A horizontal and vertical physical cabling layout
— A cabling plan for the server room
— Layouts of all MDFs and IDFs
— Work-area cable outlet identification plan

6. Security and fire prevention recommendations for server room, MDF, and IDFs
7. Electrical protection for equipment
8. An IP addressing scheme for all devices on the network
9. A cost projection for the implementation of the network, including the following:
— Equipment purchase costs
— Cabling and testing costs
— Equipment installation costs
— Training and support costs
10. A timeline for the implementation of the network
Following is a study guide that contains hints to help you complete these tasks.
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