aravinda project report

8/7/2019 ARAVINDA PROJECT REPORT

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City & Guilds Advanced Technician Diploma in

Telecommunication Systems(2730)

Implementation of a Local Area Network


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General Information

Project Title : Local Area Network

Institute : APSS International, 5, Harmers Avenue, Colombo 6, Sri Lanka.

Center Number : 844022

Contact Information:

Name : M.A. Aravinda Lakshan Dhanapala.

Enrolment Number : IHK3845

Address : 166/6, Kirillawala, Weboda, Sri Lanka.Telephone : 0777336412

E-mail Address : [email protected]
mailto:[email protected]:[email protected]


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TABLE OF CONTENTS

INTRODUCTION

WHAT IS A LOCAL AREA NETWORK?

HOW WE CAN IMPLEMENT A LOCAL AREA NETWORK?

BENEFITS OF NETWORKING

SCOPE OF THIS REPORT

PROBLEMS

SOLUTION

TECHNICAL OVERVIEW OF THE PROPOSED NETWORK ARCHITECTURE

SWITCHES

TYPES OF NETWORK CONNECTORS AND CABLES

OPTICAL FIBER TECHNOLOGY

STRUCTURED CABLING PLANNING

VLAN TECHNOLOGY


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ETHERNET TECHNOLOGY

IP ADDRESSING

PROPOSED NETWORK ARCHITECTURE

CONCLUTION

COST

RELIABILITY

TECHNOLOGY

REDUNDANCY


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INTRODUCTION

WHAT IS A LOCAL AREA NETWORK ?

A computer network that spans a relatively small area. Most LANs are confined to a

single building or group of buildings. However, one LAN can be connected to other

LANs over any distance via telephone lines and radio waves. A system of LANs

connected in this way is called a wide-area network (WAN) .

Most LANs connect workstations and personal computers . Each node (individual

computer ) in a LAN has its own CPU with which it executes programs , but it also is able

to access data and devices anywhere on the LAN. This means that many users can shareexpensive devices, such as laser printers, as well as data. Users can also use the LAN to

communicate with each other, by sending e-mail or engaging in chat sessions.

There are many different types of LANs Ethernets being the most common for PCs. Most

Apple Macintosh networks are based on Apple's AppleTalk network system , which is

built into Macintosh computers.

The following characteristics differentiate one LAN from another:

Topology : The geometric arrangement of devices on the network . For

example, devices can be arranged in a ring or in a straight line.

Protocols : The rules and encoding specifications for sending data. The

protocols also determine whether the network uses a peer-to-peer or client/server

architecture .

Media : Devices can be connected by twisted-pair wire , coaxial cables, or

fiber optic cables. Some networks do without connecting media altogether,communicating instead via radio waves.

LANs are capable of transmitting data at very fast rates, much faster than data can be

transmitted over a telephone line; but the distances are limited, and there is also a limit on

the number of computers that can be attached to a single LAN.
http://www.webopedia.com/TERM/L/computer.htmlhttp://www.webopedia.com/TERM/L/network.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/system.htmlhttp://www.webopedia.com/TERM/L/wide_area_network_WAN.htmlhttp://www.webopedia.com/TERM/L/workstation.htmlhttp://www.webopedia.com/TERM/L/personal_computer.htmlhttp://www.webopedia.com/TERM/L/node.htmlhttp://www.webopedia.com/TERM/L/CPU.htmlhttp://www.webopedia.com/TERM/L/execute.htmlhttp://www.webopedia.com/TERM/L/program.htmlhttp://www.webopedia.com/TERM/L/access.htmlhttp://www.webopedia.com/TERM/L/data.htmlhttp://www.webopedia.com/TERM/L/device.htmlhttp://www.webopedia.com/TERM/L/user.htmlhttp://www.webopedia.com/TERM/L/laser_printer.htmlhttp://www.webopedia.com/TERM/L/e_mail.htmlhttp://www.webopedia.com/TERM/L/chat.htmlhttp://www.webopedia.com/TERM/L/Ethernet.htmlhttp://www.webopedia.com/TERM/L/Ethernet.htmlhttp://www.webopedia.com/TERM/L/PC.htmlhttp://www.webopedia.com/TERM/L/Macintosh_computer.htmlhttp://www.webopedia.com/TERM/L/Apple_Computer.htmlhttp://www.webopedia.com/TERM/L/AppleTalk.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/topology.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/protocol.htmlhttp://www.webopedia.com/TERM/L/peer_to_peer_architecture.htmlhttp://www.webopedia.com/TERM/L/client_server_architecture.htmlhttp://www.webopedia.com/TERM/L/client_server_architecture.htmlhttp://www.webopedia.com/TERM/L/media.htmlhttp://www.webopedia.com/TERM/L/twisted_pair_cable.htmlhttp://www.webopedia.com/TERM/L/coaxial_cable.htmlhttp://www.webopedia.com/TERM/L/fiber_optics.htmlhttp://www.webopedia.com/TERM/L/computer.htmlhttp://www.webopedia.com/TERM/L/network.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/system.htmlhttp://www.webopedia.com/TERM/L/wide_area_network_WAN.htmlhttp://www.webopedia.com/TERM/L/workstation.htmlhttp://www.webopedia.com/TERM/L/personal_computer.htmlhttp://www.webopedia.com/TERM/L/node.htmlhttp://www.webopedia.com/TERM/L/CPU.htmlhttp://www.webopedia.com/TERM/L/execute.htmlhttp://www.webopedia.com/TERM/L/program.htmlhttp://www.webopedia.com/TERM/L/access.htmlhttp://www.webopedia.com/TERM/L/data.htmlhttp://www.webopedia.com/TERM/L/device.htmlhttp://www.webopedia.com/TERM/L/user.htmlhttp://www.webopedia.com/TERM/L/laser_printer.htmlhttp://www.webopedia.com/TERM/L/e_mail.htmlhttp://www.webopedia.com/TERM/L/chat.htmlhttp://www.webopedia.com/TERM/L/Ethernet.htmlhttp://www.webopedia.com/TERM/L/PC.htmlhttp://www.webopedia.com/TERM/L/Macintosh_computer.htmlhttp://www.webopedia.com/TERM/L/Apple_Computer.htmlhttp://www.webopedia.com/TERM/L/AppleTalk.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/topology.htmlhttp://www.webopedia.com/TERM/L/local_area_network_LAN.html#%23http://www.webopedia.com/TERM/L/protocol.htmlhttp://www.webopedia.com/TERM/L/peer_to_peer_architecture.htmlhttp://www.webopedia.com/TERM/L/client_server_architecture.htmlhttp://www.webopedia.com/TERM/L/client_server_architecture.htmlhttp://www.webopedia.com/TERM/L/media.htmlhttp://www.webopedia.com/TERM/L/twisted_pair_cable.htmlhttp://www.webopedia.com/TERM/L/coaxial_cable.htmlhttp://www.webopedia.com/TERM/L/fiber_optics.html


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HOW WE CAN IMPLEMENT A LOCAL AREA NETWORK?

To implement a local area network (LAN) there are several components that we

have to consider. Those components are;

The following are some common components you may find in a basic network:

Computer

General-purpose machine that processes data according to a set of instructions that are

stored internally either temporarily or permanently. The computer and all equipment

attached to it are called hardware. The instructions that tell it what to do are called

software. A set of instructions that perform a particular task is called a program, or

software program.


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The instructions in the program direct the computer to input, process and output as

follows:

Input/Output - The computer can selectively retrieve data into its main memory

(RAM) from any peripheral device (terminal, disk, tape, etc.) connected to it.

After processing the data internally, the computer can send a copy of the results

from its memory out to any peripheral device. The more memory it has, the more

programs and data it can work with at the same time. Storage - By outputting data onto a magnetic disk or tape, the computer is able to

store data permanently and retrieve it when required. A system's size is based on

how much disk storage it has. The more disk, the more data is immediately

available. Processing - (The 3 C's*) Once the data is in the computer's memory, the

computer can process it by calculating, comparing and copying it.

o Calculate - The computer can perform any mathematical operation on

data by adding, subtracting, multiplying and dividing one set with another.

o Compare - The computer can analyze and evaluate data by matching it

with sets of known data that are included in the program or called in from

storage.

o Copy - The computer can move data around to create any kind of report or

listing in any order.

Computers are based on digital technology; they work on the presence or absence of a

voltage on a wire, similar to a light switch. A value of 0 means no voltage is present, and

a value of 1 would be equivalent to 5 volts. Therefore, data is processed in a binary (or

base 2) numbering system. Humans are used to the decimal system (base 10). In order for

the computer to understand a value such as 25, it would need to convert the decimal valueinto binary:


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Server / Gateways

In client/server architecture, a server is a single, high-powered machine with a large hard

disk set aside to function as a file server for all the client machines in the network A

server could function as a file server, Web server, Mail server, FTP server, News server,

and many other applications.

A Gateway is a computer that performs protocol conversion between different types of

networks or applications. For example, a gateway can connect a personal computer LAN

to a mainframe network. An electronic mail gateway converts messages from two or

more different e-mail standards.

Network Interface Card

The network interface card (NIC) provides the physical

connection between the network and the computer workstation. Most NICs are internal,

with the card fitting into an expansion slot inside the computer. Some computers, such as

Mac Classics, use external boxes which are attached to a serial port or a SCSI port.

Laptop computers generally use external LAN adapters connected to the parallel port or

network cards that slip into a PCMCIA slot.

Network interface cards are a major factor in determining the speed and performance of anetwork. It is a good idea to use the fastest network card available for the type of

workstation you are using.

The three most common network interface connections are Ethernet cards, LocalTalk

connectors, and Token Ring cards. According to a International Data Corporation study,


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Ethernet is the most popular, followed by Token Ring and LocalTalk (Sant'Angelo, R.

(1995). NetWare Unleashed, Indianapolis, IN: Sams Publishing). The network interface

card (NIC) provides the physical connection between the network and the computer

workstation. Most NICs are internal, with the card fitting into an expansion slot inside the

computer. Some computers, such as Mac Classics, use external boxes which are attached

to a serial port or a SCSI port. Laptop computers generally use external LAN adapters

connected to the parallel port or network cards that slip into a PCMCIA slot.

Network interface cards are a major factor in determining the speed and performance of a

network. It is a good idea to use the fastest network card available for the type of

workstation you are using.

The three most common network interface connections are Ethernet cards, LocalTalk

connectors, and Token Ring cards. According to a International Data Corporation study,

Ethernet is the most popular, followed by Token Ring and LocalTalk (Sant'Angelo, R.

(1995). NetWare Unleashed, Indianapolis, IN: Sams Publishing).

Ethernet

Local area network (LAN) developed by Xerox, Digital and Intel. It connects up to 1,024

nodes in a bus topology at 10 Mbits per second over twisted pair, coax and optical fiber.

Faster Ethernets are coming, including Fast Ethernet, which runs at 100 Mbits per


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second, and switched Ethernet, which gives each user a 10 Mbits/sec channel. Ethernet is

the most widely used LAN. Token Ring is next.

Standard Ethernet, or "Thick Ethernet" requires a thicker coax cable, but can run as far as

1,640 feet without using repeaters. Attachment is made by clamping a transceiver, which

is cabled to the adapter card, onto the main bus cable.

Thin Ethernet, also "ThinNet" and "CheaperNet" uses a thinner, less-expensive coax that

is easier to daisy chain together using T-type BNC connectors. The transceivers are built

into the adapter cards.

Twisted pair Ethernet allows installed telephone wire to be used, and Fiber Optic

Ethernet is impervious to external radiation. Both use a star topology for easier

debugging of failed nodes. Ethernet is a data link protocol and functions at the data link

and physical levels of the OSI model (1 and 2). It uses the CSMA/CD access method and

conforms to the IEEE 802.3 standard.

Hub

Central connecting device for communications lines in a star topology. "Passive hubs"

add nothing to the data being transmitted. "Active hubs" regenerate signals and may

monitor traffic for network management. "Intelligent hubs" are computers that provide

network arrangement and may also include bridging, routing and gateway capabilities.

The hub's star topology improves troubleshooting over bus topology, in which all nodes

are connected to a common cable. Hubs can be added to Ethernet (bus) networks for

improved network arrangement. Both hubs and routers may be inserted into the middle of

a network in order to improve performance and network management.


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Router

Computer system that routes messages from one LAN (local area network) to another. It

is used to internetwork similar and dissimilar networks and can select the most expedient

route based on traffic load, line speeds and costs and network failures. Routers maintain

address tables for all nodes in the network and work at OSI layer 3. Routers are used to break apart the LAN into smaller LANs for improved security, troubleshooting and

performance. Routers with high-speed (gigabit) buses may serve as an internet backbone,

connecting all networks in the enterprise.


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DSU/CSU

(Data Service Unit/Channel Service Unit) Pair of communications devices that connect

an in house line to an external digital circuit (T1, DDS, etc.). It is similar to a modem, but

connects a digital circuit rather than an analog one. The CSU terminates the external lineat the customer's premises. It also provides diagnostics and allows for remote testing. If

the customer's communications devices are T1 ready and have the proper interface, then

the CSU is not required, only the DSU. The DSU does the actual transmission and

receiving of the signal and provides buffering and flow control. The DSU and CSU are

often in the same unit. The DSU may also be built into the multiplexer, commonly used

to combine digital signals for high-speed lines.


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BENEFITS OF NETWORKING

Most of the benefits of networking can be divided into two generic categories:connectivity and sharing . Networks allow computers, and hence their users, to be

connected together. They also allow for the easy sharing of information and resources,

and cooperation between the devices in other ways. Since modern business depends so

much on the intelligent flow and management of information, this tells you a lot about

why networking is so valuable.

Here, in no particular order, are some of the specific advantages generally associated with

networking:

o Connectivity and Communication: Networks connect computers and the users

of those computers. Individuals within a building or work group can be connected

into local area networks (LANs) ; LANs in distant locations can be interconnected

into larger wide area networks (WANs) . Once connected, it is possible for network

users to communicate with each other using technologies such as electronic mail.

This makes the transmission of business (or non-business) information easier,

more efficient and less expensive than it would be without the network.

o Data Sharing: One of the most important uses of networking is to allow the

sharing of data. Before networking was common, an accounting employee who

wanted to prepare a report for her manager would have to produce it on his PC,

put it on a floppy disk, and then walk it over to the manager, who would transfer

the data to her PC's hard disk. (This sort of shoe-based network was sometimes

sarcastically called a sneakernet.)

True networking allows thousands of employees to share data much more easily

and quickly than this. More so, it makes possible applications that rely on the

ability of many people to access and share the same data, such as databases, group


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software development, and much more Intranets and extranets can be used to

distribute corporate information between sites and to business partners.

o Hardware Sharing: Networks facilitate the sharing of hardware devices. For

example, instead of giving each of 10 employees in a department an expensivecolor printer (or resorting to the sneakernet again), one printer can be placed on

the network for everyone to share.

o Internet Access: The Internet is itself an enormous network, so whenever you

access the Internet, you are using a network. The significance of the Internet on

modern society is hard to exaggerate, especially for those of us in technical fields.

o Internet Access Sharing: Small computer networks allow multiple users to sharea single Internet connection. Special hardware devices allow the bandwidth of the

connection to be easily allocated to various individuals as they need it, and permit

an organization to purchase one high-speed connection instead of many slower

ones.

o Data Security and Management: In a business environment, a network allows

the administrators to much better manage the company's critical data. Instead of

having this data spread over dozens or even hundreds of small computers in a

haphazard fashion as their users create it, data can be centralized on shared

servers. This makes it easy for everyone to find the data, makes it possible for the

administrators to ensure that the data is regularly backed up, and also allows for

the implementation of security measures to control who can read or change

various pieces of critical information.

o Performance Enhancement and Balancing: Under some circumstances, a

network can be used to enhance the overall performance of some applications by

distributing the computation tasks to various computers on the network.

Entertainment: Networks facilitate many types of games and entertainment. The

Internet itself offers many sources of entertainment, of course. In addition, many multi-


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player games exist that operate over a local area network. Many home networks are set

up for this reason, and gaming across wide area networks (including the Internet) has also

become quite popular. Of course, if you are running a business and have easily-amused

employees, you might insist that this is really a disadvantage of networking and not an

advantage.


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SCOPE OF THIS REPORT

PROBLEMS

The goal of this project is to provide a Local Area Network (LAN) solution for a medium

scale company which has two buildings each with four floors. Both buildings are located

closely.

Currently the company has about 120 desktop computers, but does not have a computer

network.The company needs to interconnect all computers, because it needs to enhance the

efficiency of the company to provide services for its customers effectively.

SOLUTION

My work is to use this documentation to provide a Local Area Network (LAN) solution

for the company. The initial goal is to connect all computers in each building into two

switches separately by using VLAN (Virtual LAN) technology. The second goal is to

connect both switches in both buildings using the fiber optic transmission medium.

Following are the main aspects of my enterprise network solution.

1. Use Switches

2. Use Fiber Transmission Media

3. Use Structured Cabling Techniques

4. Implement Virtual LAN (VLAN)

5. Use Ethernet Technology (IEEE 802.3)

6. Use IP addressing


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TECHNICAL OVERVIEW OF THE


SWITCH

THE SWITCHING TECHNOLOGY

Local Area Network is the interface between the end user and the IT world behind. The

fundamental secret behind a good user experience is an un-congested, high performance

LAN. I proposed the LAN with Cisco Networking Equipments to address the high

availability, scalability, performance and security. The core switches which are in both

buildings are connected using two fiber optic links. Access switches which are in both

buildings are connected to core switches separately.

There are two types of switches are proposed to use for this LAN. They are,

1. Core Switches

2. Access Switches

CORE SWITCHES

I proposed Cisco Catalyst 4506 switch (6-slot) as the core switches.


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Resilient Layer 3 switching intelligent Layer 3 and 4 services

240 - 10/100/1000 connectivity

4 GbE and 2 10 GbE Uplinks

11 RU

108 Gbps Backplane

Cisco Catalyst 4506 Chassis Features

Total Number of Slots 6

Supervisor Engine Slots 1 1

Supervisor Engine Redundancy No

Supervisor Engines SupportedSupervisor Engine II-Plus, II-Plus-10GE,

IV, V, V-10GE

Line Card Slots 5

Number of Power Supply Bays 2

AC Input Power Yes

DC Input Power Yes

Integrated Power over Ethernet Yes

Minimum Number of Power Supplies 1

Number of Fan Tray Bays 1Location of 19-inch Rack-Mount 2 Front

Location of 23-inch Rack-Mount Front (option)

1 Slot 1 is reserved for supervisor engine only; slots 2 and higher are reserved for line

cards.


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10/100/1000 Ethernet port and one Small Form-Factor Pluggable (SFP)-based

Gigabit Ethernet port, with one port active at a time

Limited Lifetime Warranty

Network security through a wide range of authentication methods, data

encryption technologies, and network admission control based on users, ports,

and MAC addresses

Auto-configuration for specialized applications using Smartports

This switch has 24 Ethernet 10/100 ports and 2 dual-purpose Gigabit Ethernet uplink

ports; 1 RU.

Floor

number

Building A Building B

Number of

computers

required

Number of

Access

switches

Number of

computers

required

Number of

Access

switches1st floor 15 1 15 1

2nd

floor 15 1 15 1

3rd floor 15 1 15 1

4 th floor 15 1 15 1

Total 60 4 60 4

TYPES OF NETWORK CONNECTORS AND CABLES


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NETWORK CONNECTORS

RJ 45 Connector

Fiber Connectors

RJ 45 Connector

The RJ-45 connector is commonly used for network cabling and for telephony

applications. It's also used for serial connections in special cases.

Although used for a variety of purposes, the RJ-45 connector is probably most commonly

used for 10Base-T and 100Base-TX Ethernet connections.


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Pin #

Ethernet

10BASE-T

100BASE-TX

EIA/TIA 568AEIA/TIA 568B or AT&T

258A

1 Transmit + White with green strip White with orange stripe

2 Transmit - Green with white

stripe or solid green

Orange with white stripe

or solid orange

3 Receive + White with orange

stripe

White with green stripe

4 N/A Blue with white stripe

or solid blue

Blue with white stripe or

solid blue

5 N/A White with blue stripe White with blue stripe

6 Receive - Orange with white

stripe or solid orange

Green with white stripe or

solid

7 N/A White with brown strip

or solid brown

White with brown strip or

solid brown8 N/A Brown with white

stripe or solid brown.

Brown with white stripe or

solid brown.

Because only two pairs of wires in the eight-pin RJ-45 connector are used to carry

Ethernet signals, and both 10BASE-T and 100BASE-TX use the same pins, a crossover

cable made for one will also work with the other.
http://www.nullmodem.com/10BaseT-Crossover.htmhttp://www.nullmodem.com/10BaseT-Crossover.htmhttp://www.nullmodem.com/10BaseT-Crossover.htmhttp://www.nullmodem.com/10BaseT-Crossover.htm


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FIBER CONNECTORS

F iber-to-fiber interconnection can consist of a splice , a permanent connection, or a

connector, which differs from the splice in its ability to be disconnected and reconnected.

Fiber optic connector types are as various as the applications for which they were

developed. Different connector types have different characteristics, different advantages

and disadvantages, and different performance parameters.
http://n_window%28%27http//www.fiber-optics.info/glossary-s.htm#Splice')http://n_window%28%27http//www.fiber-optics.info/glossary-s.htm#Splice')


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Connector Insertion Loss Repeatability Fiber Type Applications

0.50-1.00 dB 0.20 dB SM, MM Datacom,


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FC

Telecommunications

FDDI

0.20-0.70 dB 0.20 dB SM, MM Fiber Optic Network

LC

0.15 db (SM)

0.10 dB (MM)0.2 dB SM, MM

High Density

Interconnection

MT Array

0.30-1.00 dB 0.25 dB SM, MMHigh Density

Interconnection

SC

0.20-0.45 dB 0.10 dB SM, MM Datacom

SC Duplex

0.20-0.45 dB 0.10 dB SM, MM Datacom

ST

Typ. 0.40 dB

(SM)

Typ. 0.50 dB

(MM)

Typ. 0.40 dB

(SM)

Typ. 0.20 dB

(MM)

SM, MMInter-/Intra-Building,

Security, Navy

ST Fiber Connector

NETWORK CABLES

CAT 5e UTP Cable


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Fiber Optic Cable

CAT 5e UTP Cable

Cat 5e cable is an enhanced version of Cat 5 that adds specifications for far end

crosstalk . It was formally defined in 2001 in the TIA/EIA-568-B standard, which no

longer recognizes the original Cat 5 specification. Although 1000BASE-T was designed

for use with Cat 5 cable, the tighter specifications associated with Cat 5e cable and

connectors make it an excellent choice for use with 1000BASE-T. Despite the stricter

performance specifications, Cat 5e cable does not enable longer cable distances for

Ethernet networks: cables are still limited to a maximum of 328 ft (100 m) in length

(normal practice is to limit fixed ("horizontal") cables to 90 m to allow for up to 5 m of

patch cable at each end). Cat 5e cable performance characteristics and test methods are

defined in TIA/EIA-568-B.2-2001.

CAT 5e UTP cable provides performance of up to 100 MHz, frequently used for both 100 Mbit/s

and gigabit Ethernet networks.

Conductor : Solid Copper Wire

Pairing :
http://en.wikipedia.org/wiki/Far_end_crosstalkhttp://en.wikipedia.org/wiki/Far_end_crosstalkhttp://en.wikipedia.org/wiki/TIA/EIA-568-Bhttp://en.wikipedia.org/wiki/Gigabit_Ethernet#1000BASE-Thttp://en.wikipedia.org/wiki/Far_end_crosstalkhttp://en.wikipedia.org/wiki/Far_end_crosstalkhttp://en.wikipedia.org/wiki/TIA/EIA-568-Bhttp://en.wikipedia.org/wiki/Gigabit_Ethernet#1000BASE-T


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Blue + White/Blue

Orange + White/Orange

Green + White/Green

Brown + White/Brown

Cabling : Four unshielded twisted pairs

Connector : RJ 45

Applications of CAT 5e Cable

Ethernet 10/100/1000 BASE-T

155 Mbps ATM

4/16 Mbps Token Ring

Analog and Digital VOIP

100 Mbps TP-PMD


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OPTICAL FIBER TECHNOLOGY

A fiber-optic system is similar to the copper wire system that fiber-optics is replacing.The difference is that fiber-optics use light pulses to transmit information down fiber

lines instead of using electronic pulses to transmit information down copper lines.

Looking at the components in a fiber-optic chain will give a better understanding of how

the system works in conjunction with wire based systems.

Light pulses move easily down the fiber-optic line because of a principle known as total

internal reflection. "This principle of total internal reflection states that when the angle of

incidence exceeds a critical value, light cannot get out of the glass; instead, the light

bounces back in. When this principle is applied to the construction of the fiber-optic

strand, it is possible to transmit information down fiber lines in the form of light pulses.


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There are two main types of optical fiber cables: single mode and multimode optical

fiber.

Single Mode Fiber

Single Mode Fiber cable is a single stand of glass fiber with a diameter of 8.3 to 10

microns that has one mode of transmission. Single Mode Fiber with a relatively narrow

diameter, through which only one mode will propagate typically 1310 or 1550nm. Carries

higher bandwidth than multimode fiber, but requires a light source with a narrow spectral

width. Synonyms mono-mode optical fiber, single-mode fiber, single-mode optical

waveguide, uni-mode fiber.

Single-mode fiber gives you a higher transmission rate and up to 50 times more distance

than multimode, but it also costs more. Single-mode fiber has a much smaller core than

multimode. The small core and single light-wave virtually eliminate any distortion that

could result from overlapping light pulses, providing the least signal attenuation and the

highest transmission speeds of any fiber cable type.

Multimode fiber

The propagation of light through a multi-mode optical fiber.

Fiber with large (greater than 10 m ) core diameter may be analyzed by geometric optics.

Such fiber is called multimode fiber , from the electromagnetic analysis. In a step-index

multimode fiber, rays of light are guided along the fiber core by total internal reflection.

Rays that meet the core-cladding boundary at a high angle (measured relative to a line

normal to the boundary), greater than the critical angle for this boundary, are completely

reflected. The critical angle (minimum angle for total internal reflection) is determined by

the difference in index of refraction between the core and cladding materials. Rays that

meet the boundary at a low angle are refracted from the core into the cladding, and do not

convey light and hence information along the fiber. The critical angle determines the

acceptance angle of the fiber, often reported as a numerical aperture. A high numerical

aperture allows light to propagate down the fiber in rays both close to the axis and at
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various angles, allowing efficient coupling of light into the fiber. However, this high

numerical aperture increases the amount of dispersion as rays at different angles have

different path lengths and therefore take different times to traverse the fiber. A low

numerical aperture may therefore be desirable.

In graded-index fiber, the index of refraction in the core decreases continuously between

the axis and the cladding. This causes light rays to bend smoothly as they approach the

cladding, rather than reflecting abruptly from the core-cladding boundary. The resulting

curved paths reduce multi-path dispersion because high angle rays pass more through the

lower-index periphery of the core, rather than the high-index center. The index profile is

chosen to minimize the difference in axial propagation speeds of the various rays in the

fiber. This ideal index profile is very close to a parabolic relationship between the indexand the distance from the axis.

Multimode fiber gives you high bandwidth at high speeds over medium distances. Light

waves are dispersed into numerous paths, or modes, as they travel through the cable's

core typically 850 or 1300nm. Typical multimode fiber core diameters are 50, 62.5, and

100 micrometers. However, in long cable runs (greater than 3000 feet [914.4 ml),

multiple paths of light can cause signal distortion at the receiving end, resulting in an

unclear and incomplete data transmission.
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Following diagram shows the structure of a Single Mode Fiber cable.


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STRUCTURED CABLING PLANNING

Horizontal Cabling System

All the UTP Data cables will be according to the star Topology. Cabling & the Termination standard will be According to TIA/EIA -568B/A

Standard.

All the horizontal cabling will be CAT6 UTP Giga Speed Cables.

All the Horizontal Cabling will be within 90 meters length.

All the Horizontal Cabling will be originated from the Switch / Patch Panel

location from the same floor Area.

All the Cabling Accessories (Patch Panel, Cables, Outlets, Patch cords And Fly

cords) will be CAT6 Standard.

Conduits are caring the UTP cables will have 40% leverage.

Only one cross connect will have between the Outlet and the Switch on the

cabling.

All the Equipment Mounting cabinets will be according the 19 EIA standard,

lockable Glass Door, Type.

All the horizontal cabling will be over 350 MHz and 24 AWG Solid Conducting

Cables.

All the patch Panels designed for Gaga speed data communication , and with

industry Standard with ANSI/TIA/EIA 568A/A compliant, 19 rack mountable

and cables guiders on the patch panel it self , and with the cables management

panel at the behind of the patch panel & Paper Numbering System.

All the Outlets will be RJ45, meet with ISO/IEC 11801:2002 Class EIA/TIA

568A/B CAT6 Compatible Fast Ethernet, And Giga Bit Ethernet.

Dual face Plates will provide for all the Out lets, for the future expansions the 6cables access cable length will be managed every data outlet.

All the UTP cables will be labeled from each end, patch panel, and on the face

plates according to the Standard numbering system.


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All the patch cords and Fly cord will be 0.9m and 3m respectively and,

Supporting up to Giga Speeds, and Factory terminated, and tested to meet

EIA/TIA 568 B-2.1 Standard.

All the UTP Outlets Will is RJ45; meet with ISO/IEC 11801:2002 Class EIA/TIA

568A/B CAT6 Compatible.

All the Racks will ground according to the TIA/EIA -607 Standards.

Fiber Backbone Cabling System

All the Switch Locations /Rack Locations will be connected according to the

Hierarchical Star Topology.

All the Indoor Fiber Cables Are according to IEEE 802.3z standards.

All the indoor Fiber Cables Are Riser rated, Tight Buffered and Consist with 08

cores.

Fiber Cables will be 50/125 microns.

All cables are Support to communicate Fast Ethernet & 10 Gigabit Ethernet.

All the Fiber Connectors will be Sc MM Simplex type.

All the Fiber Patch Panel Couplers Will is MM Duplex Type and meets the

Required Standard.

All the Fiber Cables will be labeled end to end and will be tested for continuity

before, after and will be certified for the required parameters given after the

termination.

Testing & Certification of the UTP Network and the Fiber back Bone

UTP Testing & Certification will be done by Fluke DTX 1800 Series Certification

tool & It Will test For , Wire Map, Length & Delay , NEXT, Attenuation, Return

Loss , Power Sum ELFXT, ACR, Power Sum NEXT, ELFEXT , Propagation

Delay, and the Delay Skew.

Fiber back Bone System Will Be tested By OTDR Tester. For the Following

Parameters 850, 1500 and 1550 ns.


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General

All the Partition areas will cover with 02 compartments PVC Trunking System.

Ceiling Area Cables will run through the Proper bracket System and covered withConduits.

Underground Parts will be supplied a 1X6 compartment GI Trunking System

with a lid (Same floor Lever will be maintaining)


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VIRTUAL LOCAL AREA NETWORKS (VLANs)

A VLAN consists of several end systems, either hosts or network equipment (such as

switches and routers), all of which are members of a single logical broadcast domain. A

VLAN no longer has physical proximity constraints for the broadcast domain. This

VLAN is supported on various pieces of network equipment (for example, LAN

switches) that support VLAN trunking protocols between them. Each VLAN supports a

separate Spanning Tree (IEEE 802.1d).

First-generation VLANs are based on various OSI Layer 2 bridging and multiplexing

mechanisms, such as IEEE 802.10, LAN Emulation (LANE), and Inter-Switch Link

(ISL), that allow the formation of multiple, disjointed, overlaid broadcast groups on a

single network infrastructure. Figure shows an example of a switched LAN network that

uses VLANs. Layer 2 of the OSI reference model provides reliable transit of data across a

physical link. The data link layer is concerned with physical addressing, network

topology, line discipline, error notification, ordered delivery frames, and flow control.

The IEEE has divided this layer into two sub layers: the MAC sub layer and the LLC sub

layer, sometimes simply called link layer.
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TYPICAL VLAN TECHNOLOGY

In Figure 10-Mbps Ethernet connects the hosts on each floor to switches A, B, C, and D.

100-Mbps Fast Ethernet connects these to Switch E. VLAN 10 consists of those hosts on
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Ports 6 and 8 of Switch A and Port 2 on Switch B. VLAN 20 consists of those hosts that

are on Port 1 of Switch A and Ports 1 and 3 of Switch B.

VLANs can be used to group a set of related users, regardless of their physical

connectivity. They can be located across a campus environment or even across

geographically dispersed locations. The users might be assigned to a VLAN because they

belong to the same department or functional team, or because data flow patterns among

them is such that it makes sense to group them together. Note, however, that without a

router, hosts in one VLAN cannot communicate with hosts in another VLAN.

VALN IMPLEMENTATION

This section describes the different methods of creating the logical groupings (or

broadcast domains) that make up various types of VLANs. There are three ways of

defining a VLAN:

By port Each port on the switch can support only one VLAN. With port-based

VLANs, no Layer 3 address recognition takes place, so Internet Protocol (IP), Novell,

and AppleTalk networks must share the same VLAN definition. All traffic within the

VLAN is switched, and traffic between VLANs is routed (by an external router or by a

router within the switch). This type of VLAN is also known as a segment-based VLAN .

By protocol VLANs based on network addresses (that is, OSI Layer 3 addresses)

can differentiate between different protocols, allowing the definition of VLANs to be

made on a per-protocol basis. With network address-based VLANs, it will be possible to

have a different virtual topology for each protocol, with each topology having its own set

of rules, firewalls, and so forth. Routing between VLANs comes automatically, without

the need for an external router or card. Network address-based VLANs will mean that a

single port on a switch can support more than one VLAN. This type of VLAN is also

known as a virtual subnet VLAN .


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By a user-defined value This type of VLAN is typically the most flexible, allowing

VLANs to be defined based on the value of any field in a packet. For example, VLANs

could be defined on a protocol basis or could be dependent on a particular IPX or

NetBIOS service. The simplest form of this type of VLAN is to group users according to

their MAC addresses.

BENEFITS OF VLAN TECHNOLOGY

In a flat, bridged network all broadcast packets generated by any node in the network are

sent to and received by all other network nodes. The ambient level of broadcasts

generated by the higher layer protocols in the networkknown as broadcast radiation

will typically restrict the total number of nodes that the network can support. In extreme

cases, the effects of broadcast radiation can be so severe that an end station spends all of

its CPU power on processing broadcasts.

VLANs have been designed to address the following problems inherent in a flat, bridgednetwork:

Scalability issues of a flat network topology

Simplification of network management by facilitating network reconfigurations

VLANs solve some of the scalability problems of large flat networks by breaking a single

bridged domain into several smaller bridged domains, each of which is a virtual LAN. It

is insufficient to solve the broadcast problems inherent to a flat switched network by

superimposing VLANs and reducing broadcast domains. VLANs without routers do not

scale to large campus environments. Routing is instrumental in the building of scalable

VLANs and is the only way to impose hierarchy on the switched VLAN internetwork.


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VLANs offer the following features:

Broadcast control Just as switches isolate collision domains for attached hosts and

only forward appropriate traffic out a particular port, VLANs refine this concept further

and provide complete isolation between VLANs. A VLAN is a bridging domain, and all

broadcast and multicast traffic is contained within it.

Security VLANs provide security in two ways:

High-security users can be grouped into a VLAN, possibly on the same physical

segment, and no users outside of that VLAN can communicate with them.

Because VLANs are logical groups that behave like physically separate entities, inter-VLAN communication is achieved through a router. When inter-VLAN communication

occurs through a router, all the security and filtering functionality that routers

traditionally provide can be used because routers are able to look at OSI Layer 3

information. In the case of non routable protocols, there can be no inter-VLAN

communication. All communication must occur within the same VLAN.

Performance The logical grouping of users allows, for example, an engineer

making intensive use of a networked CAD/CAM station or testing a multicast applicationto be assigned to a VLAN that contains just that engineer and the servers he or she needs.

The engineer's work does not affect the rest of the engineering group, which results in

improved performance for the engineer (by being on a dedicated LAN) and improved

performance for the rest of the engineering group (whose communications are not slowed

down by the engineer's use of the network).

Network management The logical grouping of users, divorced from their physical or

geographic locations, allows easier network management. It is no longer necessary to pull

cables to move a user from one network to another. Adds, moves, and changes are

achieved by configuring a port into the appropriate VLAN. Expensive, time-consuming

recabling to extend connectivity in a switched LAN environment is no longer necessary


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because network management can be used to logically assign a user from one VLAN to

another.

ETHERNET TECHNOLOGY

Ethernet is a large, diverse family of frame -based computer networking technologies

that operate at many speeds for local area networks (LANs). The name comes from the

physical concept of the ether . It defines a number of wiring and signaling standards for

the physical layer , through means of network access at the Media Access Control

(MAC)/ Data Link Layer , and a common addressing format.

Ethernet has been standardized as IEEE 802.3 . The combination of the twisted pair

versions of Ethernet for connecting end systems to the network, along with the fiber optic

versions for site backbones, has become the most widespread wired LAN technology. It

has been in use from the 1990s to the present, largely replacing competing LAN

standards such as coaxial cable Ethernet, token ring , FDDI , and ARCNET. In recent

years, Wi-Fi , the wireless LAN standardized by IEEE 802.11, has been used instead of

Ethernet for many home and small office networks and in addition to Ethernet in larger

installations.

The Ethernet is covered by the IEEE 802.3 standard that defines what is commonly

known as the CSMA/CD protocol. Three data rates are currently defined for operation

over optical fiber and twisted-pair cables:

10 Mbps10Base-T Ethernet

100 MbpsFast Ethernet

1000 MbpsGigabit Ethernet

Ethernets protocol has the following characteristics:
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Is easy to understand, implement, manage, and maintain

Allows low-cost network implementations

Provides extensive topological flexibility for network installation

Guarantees successful interconnection and operation of standards-compliant products,

regardless of manufacturer.

Ethernet LANs consist of network nodes and interconnecting media. The network nodes

fall into two major classes:

Data terminal equipment (DTE) Devices that are either the source or the

destination of data frames. DTEs are typically devices such as PCs, workstations, file

servers, or print servers that, as a group, are all often referred to as end stations.

Data communication equipment (DCE) Intermediate network devices that

receive and forward frames across the network. DCEs may be either standalone devices

such as repeaters, network switches, and routers, or communications interface units such

as interface cards and modems.

Throughout this chapter, standalone intermediate network devices will be referred to as

either intermediate nodes or DCEs . Network interface cards will be referred to as NICs .

The current Ethernet media options include two general types of copper cable: unshielded

twisted-pair (UTP) and shielded twisted-pair (STP), plus several types of optical fiber

cable.

Ethernet Network Topologies and Structures

LANs take on many topological configurations, but regardless of their size or complexity,

all will be a combination of only three basic interconnection structures or network

building blocks.


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The simplest structure is the point-to-point interconnection, shown in Figure 7-1. Only

two network units are involved, and the connection may be DTE-to-DTE, DTE-to-DCE,

or DCE-to-DCE. The cable in point-to-point interconnections is known as a network link.

The maximum allowable length of the link depends on the type of cable and the

transmission method that is used.

Figure 7-1 Example Point-to-Point Interconnection

The original Ethernet networks were implemented with a coaxial bus structure, as shown

in Figure 7-2. Segment lengths were limited to 500 meters, and up to 100 stations could

be connected to a single segment. Individual segments could be interconnected with

repeaters, as long as multiple paths did not exist between any two stations on the network

and the number of DTEs did not exceed 1024. The total path distance between the most-

distant pair of stations was also not allowed to exceed a maximum prescribed value.

Figure 7-2 Example Coaxial Bus Topology


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Although new networks are no longer connected in a bus configuration, some older bus-

connected networks do still exist and are still useful.

Since the early 1990s, the network configuration of choice has been the star-connected

topology, shown in Figure 7-3. The central network unit is either a multiport repeater

(also known as a hub) or a network switch. All connections in a star network are point-to-

point links implemented with either twisted-pair or optical fiber cable.

Figure 7-3 Example Star-Connected Topology

The IEEE 802.3 Logical Relationship to the ISO Reference Model

Figure 7-4 shows the IEEE 802.3 logical layers and their relationship to the OSI

reference model. As with all IEEE 802 protocols, the ISO data link layer is divided into

two IEEE 802 sublayers, the Media Access Control (MAC) sublayer and the MAC-client

sublayer. The IEEE 802.3 physical layer corresponds to the ISO physical layer.


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(indicated by a 0) or locally administered (indicated by a 1). The remaining 46 bits are a

uniquely assigned value that identifies a single station, a defined group of stations, or all

stations on the network.

Source addresses (SA) Consists of 6 bytes. The SA field identifies the sending

station. The SA is always an individual address and the left-most bit in the SA field is

always 0.

Length/Type Consists of 2 bytes. This field indicates either the number of MAC-

client data bytes that are contained in the data field of the frame, or the frame type ID if

the frame is assembled using an optional format. If the Length/Type field value is less

than or equal to 1500, the number of LLC bytes in the Data field is equal to the

Length/Type field value. If the Length/Type field value is greater than 1536, the frame is

an optional type frame, and the Length/Type field value identifies the particular type of

frame being sent or received.

Data Is a sequence of n bytes of any value, where n is less than or equal to 1500. If

the length of the Data field is less than 46, the Data field must be extended by adding a

filler (a pad) sufficient to bring the Data field length to 46 bytes.

Frame check sequence (FCS) Consists of 4 bytes. This sequence contains a 32-bit

cyclic redundancy check (CRC) value, which is created by the sending MAC and is

recalculated by the receiving MAC to check for damaged frames. The FCS is generated

over the DA, SA, Length/Type, and Data fields.


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Figure 7-6 The Basic IEEE 802.3 MAC Data Frame Format


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IP ADDRESSING

An IP address is an address used to uniquely identify a device on an IP network. The

address is made up of 32 binary bits which can be divisible into a network portion and

host portion with the help of a subnet mask. The 32 binary bits are broken into four octets

(1 octet = 8 bits). Each octet is converted to decimal and separated by a period (dot). For

this reason, an IP address is said to be expressed in dotted decimal format (for example,

172.16.81.100). The value in each octet ranges from 0 to 255 decimal, or 00000000 -

11111111 binary.

This is sample shows an IP address represented in both binary and decimal.

10. 1. 23. 19 (decimal)

00001010.00000001.00010111.00010011 (binary)

These octets are broken down to provide an addressing scheme that can accommodate

large and small networks. There are five different classes of networks, A to E. This

document focuses on addressing classes A to C, since classes D and E are reserved and

discussion of them is beyond the scope of this document.

Given an IP address, its class can be determined from the three high-order bits. Figure 1shows the significance in the three high order bits and the range of addresses that fall into

each class. For informational purposes, Class D and Class E addresses are also shown.
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Figure 1

In a Class A address, the first octet is the network portion, so the Class A example in

Figure 1 has a major network address of 10. Octets 2, 3, and 4 (the next 24 bits) are for

the network manager to divide into subnets and hosts as he/she sees fit. Class A addresses

are used for networks that have more than 65,536 hosts (actually, up to 16777214 hosts!).

In a Class B address, the first two octets are the network portion, so the Class B example

in Figure 1 has a major network address of 172.16. Octets 3 and 4 (16 bits) are for local

subnets and hosts. Class B addresses are used for networks that have between 256 and

65534 hosts.

In a Class C address, the first three octets are the network portion. The Class C example

in Figure 1 has a major network address of 193.18.9. Octet 4 (8 bits) is for local subnets

and hosts - perfect for networks with less than 254 hosts.
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Network Masks

A network mask helps you know which portion of the address identifies the network and

which portion of the address identifies the node. Class A, B, and C networks have default

masks, also known as natural masks, as shown here:

Class A: 255.0.0.0

Class B: 255.255.0.0

Class C: 255.255.255.0

An IP address on a Class A network that has not been subnetted would have an

address/mask pair similar to: 8.20.15.1 255.0.0.0. To see how the mask helps you identify

the network and node parts of the address, convert the address and mask to binary

numbers.

8.20.15.1 = 00001000.00010100.00001111.00000001

255.0.0.0 = 11111111.00000000.00000000.00000000

Once you have the address and the mask represented in binary, then identifying the

network and host ID is easier. Any address bits which have corresponding mask bits set

to 1 represent the network ID. Any address bits that have corresponding mask bits set to 0

represent the node ID.

8.20.15.1 = 00001000.00010100.00001111.00000001

255.0.0.0 = 11111111.00000000.00000000.00000000

-----------------------------------

net id | host id

netid = 00001000 = 8

hostid = 00010100.00001111.00000001 = 20.15.1


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Understanding Subnetting

Subnetting allows you to create multiple logical networks that exist within a single Class

A, B, or C network. If you do not subnet, you will only be able to use one network from

your Class A, B, or C network, which is unrealistic.

Each data link on a network must have a unique network ID, with every node on that link

being a member of the same network. If you break a major network (Class A, B, or C)

into smaller subnetworks, it allows you to create a network of interconnecting

subnetworks. Each data link on this network would then have a unique

network/subnetwork ID. Any device, or gateway, connecting n networks/subnetworks has

n distinct IP addresses, one for each network / subnetwork that it interconnects.

To subnet a network, extend the natural mask using some of the bits from the host ID

portion of the address to create a subnetwork ID. For example, given a Class C network

of 204.15.5.0 which has a natural mask of 255.255.255.0, you can create subnets in this

manner:

204.15.5.0 - 11001100.00001111.00000101.00000000

255.255.255.224 - 11111111.11111111.11111111.11100000

--------------------------|sub|----

By extending the mask to be 255.255.255.224, you have taken three bits (indicated by

"sub") from the original host portion of the address and used them to make subnets. With

these three bits, it is possible to create eight subnets. With the remaining five host ID bits,

each subnet can have up to 32 host addresses, 30 of which can actually be assigned to a

device since host ids of all zeros or all ones are not allowed (it is very important to

remember this). So, with this in mind, these subnets have been created.

204.15.5.0 255.255.255.224 host address range 1 to 30







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of 255.255.255.224 (/27) allows you to have eight subnets, each with 32 host addresses

(30 of which could be assigned to devices). If you use a mask of 255.255.255.240 (/28),

the break down is:

204.15.5.0 - 11001100.00001111.00000101.00000000

255.255.255.240 - 11111111.11111111.11111111.11110000

--------------------------|sub |---

Since you now have four bits to make subnets with, you only have four bits left for host

addresses. So in this case you can have up to 16 subnets, each of which can have up to 16

host addresses (14 of which can be assigned to devices).

Take a look at how a Class B network might be subnetted. If you have network

172.16.0.0 ,then you know that its natural mask is 255.255.0.0 or 172.16.0.0/16.

Extending the mask to anything beyond 255.255.0.0 means you are subnetting. You can

quickly see that you have the ability to create a lot more subnets than with the Class C

network. If you use a mask of 255.255.248.0 (/21), how many subnets and hosts per

subnet does this allow for?

172.16.0.0 - 10101100.00010000.00000000.00000000

255.255.248.0 - 11111111.11111111.11111000.00000000

-----------------| sub |-----------

You are using five bits from the original host bits for subnets. This will allow you to have

32 subnets (2 5). After using the five bits for subnetting, you are left with 11 bits for host

addresses. This will allow each subnet so have 2048 host addresses (2 11), 2046 of which

could be assigned to devices.


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aravinda project report

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