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The standard specifies minimum requirements for telecommunications cabling, recommended topology and distance limits, media and connecting hardware performance specifications, and connec

F.A.R.B Case Study

F.A.R.B Software Development, LTD.: Network Design and Implementation

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

Overview

Students completing this case study should be able to:

■ Gather information for the pre-installation 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

These objectives are spelled out within this case study in a letter from Cheryl Farb, President, FARB Software Development LTD., which for this case study is serving as the client company

General Design Process Framework

Network design is best done by following a framework To determine where the wires go requires knowledge of the structure to be

networks You will need to know where the users are, and what their applications are, in order to begin to sketch out a viable network A layer one LAN logical and physical topology must be developed This development includes the type of cable and the physical (wiring) topology that are selected, and 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 micro-segmentation, VLANS, and STP, to add efficiency and reliability

A Layer 3 hierarchical plan is then 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 where routing and firewalls are implemented imposing a logical structure on the network They can also 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, moves strictly to software, and controls access and availability of the network It involves access lists and firewall configuration While a complete network design will keep moving up the OSI model, it is beyond the focus of this project This design will focus 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

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

Pre-design process

Before a network can be designed, the data needed to design the network must be gathered In order for a network to be effective and serve the needs of its users, it 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:

■ 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

communications from the president outlining of F.A.R.B Software Development, LTD

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 projected requirements gathered in the first step This step will identify and define issues or problems that need to be addressed (e.g a remote room in the building may not have network access) It will also provide information about future network expansion needs, access, and security

The third step is to identify the resources and constraints of the organization Organization 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 must

be documented Identification and the definition of those projected needs must also be done The answers to some of these questions will also help determine how much training will be required, and how many people will be needed to support the LAN The questions asked should include:

■ 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 communications model Using the OSI model

as the framework, an understanding of the functions and devices that support operations at those layers should also 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, there are rules and standards that govern how a network is designed and built These rules and standards must be learned before the actual case study can be performed

Students completing this lesson should be able to:

■ Develop a Layer 1 and 2 topology

■ Gather information for both the pre-process and the process

■ Create documentation during the course of the process

■ Comply with TIA, EIA, and electrical standards

Please 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 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

Web link:

http://www.rvcomp.com/wiring/EIA/organizations_codes.htm

Standards Definitions

The primary standards that will affect layer design have been created

by the TIA/EIA The Telecommunications Industry Association (TIA) and Electronic Industries Alliance (EIA) are trade associations that jointly develop and publish a series of standards 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 Prior to that, AT&T used proprietary cables and systems Both TIA and 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 are often 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 former Commercial Building Standard for Telecommunications Wiring There are several supplements covering some of the newer, faster copper media The standard and all of its supplements have been replaced by TIA/EIA-568-B

TIA/EIA-568-B is the current Cabling Standard The standard specifies minimum requirements for telecommunications cabling, recommended topology and distance limits, media and connecting hardware performance specifications, and connector and pin assignments This standard specifies the component and transmission requirements for media TIA/EIA-568-B.1 specifies a generic telecommunications cabling system for commercial buildings that will support a multi-product, multi-vendor environment TIA/EIA-568-B.1.1 is an addendum that applies to 4-pair unshielded twisted-pair (UTP) and 4-twisted-pair screened twisted-twisted-pair (ScTP) patch cables bend radius TIA/EIA-568-B.2 specifies cabling components, transmission, system models, 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 telecommunications 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 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, defacement, and adhesion requirements as specified in UL969

TIA/EIA-607 is the standard for Commercial Building Grounding and Bonding Requirements for Telecommunications supports a multi-vendor, multi-product environment, as well as the grounding

practices for various systems that may be installed on customer 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 speaking, electrical current follows the path of least resistance Because metals such as copper provide little resistance, they are frequently 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 are

frequently used as insulators They are used to insulate conductors to prevent shock, fires, and short circuits

There are many different shapes of electrical outlets 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 The purpose

of connecting the safety ground to computing equipment is to prevent people from being exposed to hazardous voltage resulting from a wiring fault inside the device

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 build up of hazardously high voltages The circuit links directly to the hot connection to the earth

Telecommunications Room Requirements

Layer one design is the largest component of the total network design It involves the implementation of the preliminary designs gathered in the pre-process phase of the network 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 cable selection 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 telecommunications room location, design, and installation

Entrance facility

The entrance facility (EF), or demarcation point (demarc), also called the point of presence (POP) or minimum point of entry (MPOE), provides the point at which outdoor cabling interfaces with the intra-building backbone cabling It represents the boundary between the service provider's responsibility and that of the customer In many buildings, this is the same point of presence (POP) for other utilities like electricity and water

The service provider is responsible for everything from the demarc 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

TIA/EIA-569-A specifies the standards 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 larger than 2,000 usable square meters, a locked, dedicated, and enclosed room is recommended The following are general guidelines when setting up a demarcation point space:

■ One square meter of plywood wall mount should be allowed for each 20 square meter area of floor space

■ Surfaces that must be covered with plywood are painted with a fire retardant paint

Telecommunications and equipment rooms

After the cable enters the building through the demarc, it travels to the telecommunications room, also called the main distribution facility (MDF) This is the center of the voice and data network A telecommunications room, or TR, is the area within a building that houses the telecommunications cabling system equipment This includes the mechanical terminations and/or cross-connect for the horizontal and backbone cabling system It would be common for departmental or workgroup switches, hubs, and possibly routers to be located here

The equipment room is a similar room that may exist in larger networks or in companies that specialize in telecommunications An equipment room is essentially a large telecommunications room that may house the main distribution frame, PBXs, 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

When designing a network, some designers will include both a telecommunications room and an equipment room depending on the amount of equipment and the needs of the customer In this module, the telecommunications room is used to house the wiring and equipment Regardless of whether there are separate rooms, both must conform to the standards produced by TIA/EIA-569-A, which are explained throughout this lesson

There are several factors that need to be considered when planning a network The first is placement of the TR, since this space contains the networking cables and devices used Accessibility and security are other factors to consider A TR should be easily accessible, but it

is a vulnerable point in the network and should be well secured A disgruntled employee or someone intent on mischief can disable an entire network with a few seconds of work in the TR Whether a TR

is a dedicated room or a part of another room, it should be physically secure

Location restrictions and size requirements

TRs should be located away from sources of electromagnetic interference like transformers, motors, x-ray, induction heaters, arc welders, radio, and radar Water is another potential problem, so rooms with water pipes are best avoided, with the exception of a sprinkler system, which may be required by local fire codes A dry gas fire suppression system is often used in place of a water sprinkler system It will prevent any serious risk of damage by extinguishing a fire without the use of water

In many cases, the demarc space contains both water and electromagnetic sources, so it is not an ideal room for housing wiring and networking devices This is the reason why most network equipment is housed away from the space where the utilities (power, water, and telephone) enter the building

In office buildings there is a need to have a TR on each floor The TR

on each floor is the junction between backbone and horizontal cabling It can contain both voice and data telecommunications equipment, termination blocks, and cross-connect wiring More than one TR per floor is required if the distance to a work area exceeds 90

m (295.3 ft), or if floor area served exceeds 1,000 square meters TIA/EIA-569 specifies that the size of a TR must be at least 3.0 m x 3.4 m (9.8 ft x 11.2 ft) for each 1,000 square meters of work area served

Room and equipment access

TIA/EIA-569 specifies the size of the door and the type of locks used for a TR The door of a TR should be at least 0.9 m (3 ft) wide and should swing open out of the room This ensures an easy exit for workers It also ensures against injury or upset equipment should someone open the door suddenly The lock should be located on the outside of the door, but should allow anyone who is on the inside to exit at any time

A wiring hub and patch panel may be mounted to a wall with a hinged wall bracket or with a distribution rack 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 workers and repairmen 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 a distribution rack is used it must have a minimum 15.2 cm (6 in)

of wall clearance for the equipment, plus another 30.5-45.5 cm (12 - 17.9 in) for physical access by workmen and repairmen A 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)

Walls, floor, and ceiling specifications

If there is only one TR in a building, then the floor on which it is located must be able to bear the load specified by the installation instructions included with the required equipment, with a minimum capability of 4.8 kPA (kilopascal), equivalent to 100 lb/ft² Where the

TR serves as a secondary TR, the floor must be able to bear a minimum load of 2.4 kPA (50 lb/ft2)

A minimum of two walls should be covered with 20 mm AC plywood that is at least 2.4 m (8 ft) high If the TR serves as the primary TR for the building, then the telephone point of presence (POP), or demarc, may also be located inside the room In such a case, the interior walls of the demarc, behind the PBX, should be covered from floor to ceiling with 20 mm plywood A minimum of 4.6 m (15 ft) of wall space should be provided for the terminations and related equipment

In addition, fire prevention materials that meet all applicable codes (fire-rated plywood, fire-retardant paint on all interior walls, and so on) should be used in the construction of the telecommunications