Traning Report PDF
Traning Report PDF
Traning Report PDF
On
“Hardware & Networking”
Diploma In
Electronics & Communication Engineering
Year 2008-09.
Submitted By:
Submitted To
EITL is the IT division of the Elecon group of companies and has an experience of more than
13 years in the field of hardware, software and networking solutions. Situated in the
heart of Vithal Udyognagar an Industrial Estate and in the proximity of the
educational town of Vallabh Vidyanagar, EITL is all set to reach new heights in the
field of IT solutions.
We are a professional team providing IT solutions to enable businesses and
organizations to respond proactively to the demands of emerging global business
scene. Through the intelligent and relevant application of technology in a diversity of
situations, EITL plans to help businesses and organizations push the limits of
excellence, optimizing their strengths to achieve their goals.
ENGINEERING SERVICES:
Based on a combination of engineering knowledge, software services, and industrial
experience, EITL offers a wide spectrum of engineering software services in the areas
of CAD/CAM/CAE. We undertake Product Design and Analysis using C.A.D.
software like:
SDRC IDEAS Master Series
AutoDesk Mechanical Desktop 2000 and AutoCAD 2000
SDRC PDM
TRAINING SERVICES:
Hands-on training (functional / tools)
Workflow Management
on ERP (Baan & Oracle)
Lotus Domino R5 Installation and Configure
NETWORKING SERVICES:
These services enable corporate to set up LAN/WAN/ MAN/VPN networks to
connect various offices, branches, and users across various locations
The Network Solutions group has Cisco, AVAYA and Microsoft Certified
Professionals who execute complex networking solutions - voice / data networks,
leased lines, ISDN connectivity, network security, etc.
Network Performance & Security Audit
ACKNOWLEDGEMENT
We would like to express my deep sense of gratitude to Mr. Pankaj Patel and all engineers
for giving me an opportunity to do training at ELECON INFORMATION
TECHNOLOGY LIMITED.
We got the good knowledge of trouble shooting of hardware, networking related problems
and connecting local area networking. We feel very lucky to undergo training in such
organizing. They have shown us right path that we could follow in the future to reach
maximum possible heights in my life.
Finally, we like to thanks all staff member of EITL for their very good support during my
training.
PREFACE
The basic goal of the information technology is to efficiently capture and organize the
available information in a manner that would avail the management to concretes more on
decisional issue rather than daily business chores. This has been very important factor in the
growth of computer technology and its quick amalgamation with the different business
process.
It has rich experience to work in a technically advance environment EITL. A student gets a
valuable experience of various business processes, System development methodologies and
strategies. This project is the part of the second semester study, which gives me valuable
opportunity to implement theoretical knowledge into practical life.
The project duration was Three & Half month. This commenced from 9 th February to 23rd
May 2009.
COMPANY ABSTRACT
2. Classification Of Computers 4
CPU Box 7
Motherboard 8
Processor 10
Keyboard 12
Mouse 18
Ports(Connectors) 19
Interface cards 21
Hard Disk 26
Printer 34
5. Memory 38
8. Booting A Computer 48
Introduction
HARDWARE
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INTRODUCTION
The term computer has been borrowed from compute that means – to calculate. Whereas,
initially computer were use to perform arithmetic calculation as fast speed, now they are use
to nearly every field. You can use computer for banking application, word processing,
desktop publishing, weather forecasting, railway reservation, control of machines or robot in
factories, scientific research, etc. in brief a computer may be define as a device that receive
some kind of data, analysis it, and than applies a predefine set of instruction to it to produce
some kind of output. For instant evasion in the computer. The computer then analysis the data
fed by the operator and makes a reservation. Then it prints a ticked for you. The ticket is the
output generated by the computer based on the reservation request entered by the operator. It
is also said that the computer is a data processor, because it can receive, store, processes and
retrieve any kind of data. For instant you can store the names and addresses of all employees
working in a company in a computer file. Latter, you can ask the computer to print list of
only those employees who work in the accounts department
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Chapter 2
Classification
Of
Computers
HARDWARE
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CLASSIFICATION OF COMPUTERS
Although a clear cut classification of computer is difficult, computer can be broadly classified
on the basis of purpose, components and size and processing power.
PURPOSE
Analog Computers
Digital Computers
Hybrid Computers
ANALOG COMPUTER
Analog computers are computers that measure physical quantities (e. g. Pressure,
temperature, length etc. ) and the convert them to numeric values. For example a
thermometer does not perform calculations but measures the temperature of the body by
comparing the relative expansion mercury.
Uses: Analog Computer is used mainly for scientific and engineering purpose because
they deal with quantities that very constantly. They give only approximate result.
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DIGITAL COMPUTER
Most computers are digital device. i. e. they process information using numbers which is
essentially in a binary or two state formats.
Uses: special purpose digital computers can be fixed permanently into the machine. For e.g.
processor that are installed in automobiles to be control fuel, braking system etc.
General-purpose digital computers can be used in different application since they can be store
different sets of instructions and programs.
HYBRID COMPUTERS
The features of analog and digital machines are combined to create a hybrid computing
system. For e.g. analog devices measure a patient‘s vital signs like temperature, heart
functions etc. these are then converted to numbers and supplied to the digital components that
monitor the patient‘s vital signs. Any fluctuations can be thus noticed immediately.
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Chapter 3
What Is
Personal Computer?
HARDWARE
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Motherboard
System Cabinet
Processor
SMPS
Keyboard
Mouse
Video Display Unit (Monitor)
Floppy Disk Drive(s)
Hard Disk Drive(s)
Printer
CD Drive
Normally a PC also has a Printer. Your PC may also have other devices such as the compact
Disk (CD) Drive, Scanner, Zip Drive, etc
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CPU BOX
The CPU box houses the heart and brain of the computer. All electronic circuit, power
supply, floppy drive(s), and hard drive(s) are housed in this box. The shape and the size of the
box may differ from the computer to computer. However, they all have the same electronic
circuit and parts inside. The storage unit of the memory of the computer is also in the same
box. The primary memory of the PC is housed on the electronic circuit board kept in this box.
These boards are not visible from the outside. The CPU box also houses the floppy disk
drive(s) and Hard disk drive(s) that from the secondary memory
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CABINET
Computer cabinet are fitted with doors and side panels(Which may or may
not be removable).Cabinets enclose a rack,which is a frame that provides a means for
mounting electronic equipments come in a variety of styles,colors,and many contain
baffles,fans and other features.
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MOTHERBOARD
The motherboard is a circuit on which all the electronic components of computer are
connected. This include both internal parts of the system unit like Processor, display card of
the monitor, sound card, memory etc and the connector of external parts like mouse,
keyboard, hard disk, floppy disk etc. The ‗ports‘ and ‗slots‘, which connect these
components, also exist in the motherboard. The circuits in the motherboard help in data
transfer among the components. Bios, RAM slots and Chipset are too mounted on the
motherboard.
Motherboard Components:
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Motherboard Layout
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Processor
One of the most important parts of computer called as heart of computer. The brain of a
computer is it processor. The processor in a modern computer is an Integrated Circuit (IC)
chip.
the data obtained through input devices and transfer the result to the output units. Processors
from different companies are available today. Intel-PentiumIV, Xenon,Celeron,AMDAthlon,
Cyrix M3 etc. are popular.
Arithmetic and Logic Unit & Control Unit (ALU & CPU)
The two main parts of a processor are Ariyhmetic and Logic Unit(ALU) and Control
Unoit(CU).The function of the ALU is to do the processing and mathematical calculations of
the information obtained through input devices.
The control unit sorts this information and sends it to the different parts of the computer
like the manager of an office.The control unit organizes and coordinates various functions of
a computer.The orderly and fast functioning of a computer indicates the efficiencyof the
control unit.
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A fan is often fixed on the processor to remove the heat generated by continuous
activity. This is known as the processor fan.
Processor Socket: The processor socket is used ti fix the processor in a computer. Different
kinds of motherboards are available today, depending upon the size and the no. of pins in a
processor,
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KEYBOARD
The keyboard of a computer looks quite similar to the keyboard of a typical typewriter. The
keyboard may have 84, 101, or 104 keys. The keys on the computer keyboard are arranged in
the same order as on the keyboard of an ordinary typewriter. There a few additional key on
the computer keyboard.
The keyboard contains alphanumeric keys to enter the string and the numbers. For the
frequent calculation and the numerical entries, numeric pad is provided. There are also
function keys. Use of them is to perform specific function with a single key stroke.
KEYBOARD FUNCTION
Generally the key switches are connected in a matrix of rows and columns. Each key has
fixed set of coordinates.
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KEYBOARD INTERFACE
The keyboard interface receive the scan mode in the serial format from the keyboard,
assemble the serial data in to a parallel d8 bit scan code, and generate the interrupt request to
the interrupt to the logic, the system switch follows specific protocol with the microprocessor
on board, for data transfer and the control sequences. The keyboard interface hardware
consists of following functional section.
The serial to parallel converter is enabling by the switch. Once the scan mode is assembled
interrupt, request and is generated. The request freezes the shift register. The interrupt service
routine enabled the shift register output which is connected to the input of the motherboard
PPI> subsequent the service routine reads this scan code through port A. the interrupt service
routine also clear the shift register as to prepare it for next scan code.
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KEYBOARD PROBLEM
Optimal Pressure
Although the computer keyboard is similar to the mechanical type writer keyboard. It is an
electronic equipment and requires more gentle handling than a mechanical keyboard. The key
switches are soft touch keys and the excessive pressure on the key top may cause damage to
the computer keyboard.
Dust
Most of the familiar occurs due to the minor problems like dust. These keys will not make
proper contact due to dust. It is advisable to cover the keyboard when not in use and clean it
once in the mouse with the small vacuum cleaner.
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Liquid
This occurs when someone accidentally spills a liquid on the keyboard while the computer
running. Cleaning the keyboard is not and easy job. And something this may result in damage
to the electronic circuitry inside. If there is nay liquid spill, the computer should be switch off
and the liquid cleaned immediately with a clean cloth. The computer should be switches ON
only when the keyboard is dry.
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When you type text through the keyboard, it is not directly printed on the sheet of paper.
Instead, it is display on a Video Display Unit (VDU) or Monitor that looks similar to an
ordinary television screen. The current typing position on the screen is informed through a
special character displayed on the screen. This special character is called cursor. The cursor
can have different shapes in different programs. However, its usual shape is blinking / non-
blinking vertical I beam, the underscore character (_) or the solid rectangle. The cursor is
shown on the monitor where the next typed ( Keyed-in) character will be accepted and
displays. When you type a character, it is display at the cursor position and the cursor
advances to the next position on the monitor.
A monitor is an output system. It main work is to display the characters. A video monitor is
like and color television without the circuitry for receiving station and also audio section.
The IBM monochrome and the color displays are based on the CRT video technology.
Inside there is electron gun that forces a stream of electrons at the screen to recharge
each dot. The screen is coated with the phosphor substance that glows for a short time
when hit by the electrons. The electrons beams scans in the horizontal direction across
the screen one line at a time. As the line is scanned the scream of electron as turned
ON or OFF at controlled times. When they on a small spot (pixel) are formed and
screen glows. The pixels are used to create an image on the screen.
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TYPES OF MONITORS
a. Digital or TTL
b. Analog
It is difficult to distinguish a digital monitor from a analog monitor just by looking at the
CRT type.
Analog monitors have better quality of phosphors coating on the inside of CRT as
compared to that of digital monitor.
The video signal is that the digital monitor is of TTL positive type while in analog
monitors. It is of both type of TTL positive and TTL negative.
The horizontal frequency in the analog monitor is between 29 KHz and 38 KHz,
which makes in usable in the various types of modes. In the digital monitor the
frequency 18.432 KHz in CGA mode.
The vertical scanning frequency in analog monitors ranges from 49 to 95 Hz.
Analog monitors have a 40 MHz band.
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MOUSE
Mouse is a device that is used in the window based program. The mouse acts as an interface
between the PC and the User. You can move the mouse to move the cursor. Select option and
to execute commands, as an alternative to entering command through the keyboard. The
mouse can have a different shapes and sizes. Your mouse has two or three buttons.
The mouse is kept on a flat surface. When you move the mouse on the surface, the Mouse
Pointer also moves in the same direction in the screen. Thus you can move the mouse pointer
on the desired commands or option display on the monitor. To select command or option you
can press the corresponding mouse button and then release it. Pressing mouse button is also
called Clicking. Most of the time, you will also use the left mouse button to select the
commands or option. The right mouse button is sometimes used by some programs to
perform specific function.
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Ports (Connectors):
A computer system becomes complete only when different parts are put together and they
communicate properly. The connection of the parts within and outside the system unit is done
using ports or connectors. These ports are connected directly to the motherboard or through
add-on cards. The internal communication in a motherboard takes place through the tiny
circuits printed on it. we can connect a computer to another computer to an input-output
device or to data storage device. Let us study different kind of ports.
1) IDE Port:
Integrated device electronics (IDE) is used to connect a hardisk, CDROM drive, CD-
Writer or a DVD drive to a motherboard. There are two such ports in a motherboard-primary
and secondary. Two devices can be connected to each port.
The floppy disk drive connector is used to connect a floppy drive to the motherboard.
The size of the FDD connector and the no. of pins in it are smaller than those of an IDE
connector.
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3) Serial port:
Serial Port is used to connect the mouse & modem. They are called COM1 &
COM2.‘COM‘ is the short form of communication. Usually in a communication port there
are either 9 or 25 pins.
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4) Parallel Port:
In a parallel port, there are holes to connect pins. Subsidiary gadgets like printer,
scanner etc. are connected through the parallel ports.
5) USB Port:
Universal serial bus(USB) port is a kind of port available in modern computers. Many
devices can be connected in series on the same USB.In comparison with serial and parallel
ports, a large amount of data can be transferred at a very high speed through USB ports. All
peripherals like printer, modem and scanner are now available in versions that can be
connected to the USB port.
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Interface Cards
An Interface Card is a circuit board that fits into an expansion slot. Examples of Interface
Cards are:
This is used for connecting the PC to LAN. Every PC is connected to the LAN by some
cables, such as Twisted Pair cables, thick or thin coaxial cable, and fiber optic cable.
Each LAN adapter card must have a connector compatible with the type of LAN
cabling used.
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2) Sound Card:
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3) Video Card
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The computer would be very incomplete without the floppy drives. A floppy disk allows
information to be exchanged between two computers. All that needs to be done is to insert a
floppy in the drive, copy the date from the hard disk to the floppy, and insert in it the machine
where that data is required. It is still one of the easier and cost effective ways to exchange
information or data between two computers.
The floppy is actually enclosed in a plastic jacket that protects if from heat, dust and
electrical shocks. When a floppy is expressed to any of the above, two things can be happen :
The floppy can be physically damaged, which can lead to loss of the data which is on
the floppy.
The floppy may remain intact, but there may still be a data loss.
The Floppy Disk Drives is an important input / output ( I / O ) device in the PC. ( The I / O
device is used for inputting (reading) and storing (Writing) information. The PC contains one
or more floppy disk device. The floppy disk drives are a storage device. It stored the
information (Documents) on the floppy diskettes. That is inserted in the floppy disk drives.
The floppy diskette is usually called floppy disk or just disk (Disc). The PC stores all types of
information, such as letters, computer programs, spreadsheet, databases, etc. in the floppy
disk. When the PC requires the information stored in the floppy disk, it reads the information
back through the floppy disk drives. On the other word, the floppy disk drives are a storage or
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reading / writing device and the floppy disk is storage medium. If you do not need the
information stored on a disk any more, you can erase it. In this way, you can make room to
store new information on the same disk.
The floppy disk is flexible plastic that has magnetic coating on one or both sides. This plastic
disk enclosed inside another square plastic jacket. Two of floppy disk is used in PCs. :
Beside the size, a micro floppy differs from a mini floppy disk in the following counts :
The micro floppy disk is more rugged than the mini floppy disk. Where as the mini
floppy disk uses a flexible jacket (outside cover), the micro floppy disk uses a rigid plastic
cover.
For the performing read or write operations, there is the small opening in the jacket of
the mini floppy disk. Thus the magnetic disk in the mini floppy is always exposed to the
environment through this opening in the micro floppy is covered with a shield. This shield
protects the disk from the dust. When you insert the micro floppy disk in the floppy drive.
The drive automatically opens the shield to perform the read or write operation.
the write protect notch in a micro floppy disk has a built-in tab. You can use this tab to
disable writing on the disk.
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The floppy disk interface uses what is considered,by most people,a truly strange cable.It
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HARD DISK
Unlike a floppy disk that is flexible and removable, the hard disk used in the PC is
permanently fixed. The hard disk has storage capacity of 10 MB (10,000,000 bytes or
character) or higher. The hard disk used in a higher end PC can have a storage capacity of up
to 80 GB ( Giga Bytes; 1GB = 1000 MB ). Now-a-days, hard disk capacities of 540 MB, 1
GB, 1.6 GB, 2 GB, 4 GB, 8 GB, 10 GB, 20 GB, 40 GB are quite common. The data transfer
rate between the CPU and hard disk is much higher as compared to that between the CPU and
floppy disk Drives. The CPU can use the hard disk to load programs and data. As well as to
store data, the hard disk is very important input/output (I / O) device. The hard disk drive
does not require any special care except that one should operate the PC with a hard disk in a
dust free and a cool room (preferably Air – Conditioned).
The head can read / write from a portion of platter rotating beneath it. Data id organized in a
set of concentric rings called tracks. Each track is the same width as the head. The same
numbers of bits are typically stored on each track. Thus the density increases towards the
innermost tracks.
Data is stored and retrieved from the disk in blocks. Data is stored in block-size regions
called sectors. The sector may be of fixed or variable length. Adjacent sector are separated by
intra-track gaps. Certain control data is recorded on the disk to identify the start and end point
of a sector. The data is recorded during formatting and is used only by the disk drive. It is not
accessible to the user.
The head may be fixed or movable. In a fixed-head disk there is one read/write head per
track. The heads are mounted on a rigid arm. A shaft that rotates the disk and electronics
required for the input and output of the binary data.
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A set of corresponding tracks on all structure of the disk pack equidistant from the spindle is
called a cylinder.
Commands to read or write are received from the computer by the disk controller. For writing
on the disk pack the computer specifies the drive number, cylinder number, surface number
and sector number. The disk controller position ate arm assembly so that the read / write head
reaches the specified cylinder. The time taken to the reach the specified cylinder is called the
seek time. Seek time varies depending on the position of the arms assembly when the read /
write command is performed. Maximum seek time is taken when the arms assembly has to
move from the outer most track to the inner most track. Minimum seek time is taken when
the arms assembly is already positions over the required cylinder.
Track
s
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Tracks
Switching is the process of switching the read / write head from one sector to another and it is
an electronic and instantaneous operation. After the head is selected there is further delay –
rotational latency. Because the required sector must reach the read / write head.
Thus,
Average access time = average latency + average seek time.
Once the sector is reached. Data is read at the speed determined by the rotational speed of the
disk.
The full set of these platters and the read and write heads are enclosed in a vacuumed
container, to protect it from dust and electric shocks. When the hard disk being accessed, it
makes a peculiar groaning sound. This indicates that the hard disk drive is an example of a
device that is both mechanical and electronic.
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Hard disk is sealed unit that holds most of the in a computer system. A hard disk drive is
made up of many components may be of various types such as ESDI ( Enhanced Small
Device Interface ), SCSI ( Small Computer System Interface ) etc.
Disk Plotter
Read / write head
Head Actuator ( Stepper or Voice Coil )
Spindle Motor
Logic Card
Cables & Connector
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The plotters, spindle motor, head mechanism are usually contained in a shielded chamber,
called hard disk assembly. A typical hard disk has one or more plotters. These entire plotters
are mounted on a single shaft, and driven by the spindle motor. The plotter about 0.05 inch
and coated with a magnetically retentive substance or media, which is actually responsible for
storing the data. The thickness of this media is above 30 microns.
The hard disk drive has one read / writes head for each plotter surface. All the heads are
mounted on a common movement mechanism. Each head is mounted on an arm that is
spring loaded to force the heads on the plotters. At the rest the heads are in contact with the
plotters. But when the drive is spinning at full speed air pressure is formed below the head
which lefts it away from plotter.
The electromechanical mechanism that bends to move the head assembly is called the
actuator. In a stepper motor type a stepper motor that used metal bend to move the head
assembly from the outer edge of plotter to its inner edge achieves actuator the movements. In
a voice coil type a actuator, the similar movement of head assembly by using the voice coil.
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There are few steps users have to remember before formatting and partitioning a hard disk s
listed bellows:
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Then System asks you how much size you want to specify for Primary Dos Partition. The
user can give value size of Partition in to percentage or in Numeric Value.
9. After create a Primary Partition make this Partition active using 2 option on main
screen.
10. Then Create Extended Dos Partition and Logical Drives in Extended drive into it. Enter
Volume Label when Necessary.
11. After Creation of Primary and Extended Dos Drives, Format All Drives that you
Created.
12. Then using Esc key goes out Fdisk command area.
13. Then find the volume label of CD – ROM, enter into and find setup path and write
setup, press enter; now installation of OS will start automatically.
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PRINTER
The printer is an output device that is used to print documents on paper. Various kinds of
printers are used with PCs. The Dot Matrix Printer (DMP) contains a few tiny needles. There
art 7 or 8 needles in a low quality DMP and up to 24 needles in a high quality DMP. At the
time of printing, as the head moves from one end of the paper to other, these needles are fired
selectively to print different character or graphics. Dot Matrix Printers usually have a printing
speed of 100 to 500 characters per second.
Inkjet / DeskJet printer are also fast becoming a popular choice for the use with the PCs.
These printer offers good quality and noiseless operation. These are non-impact types of
printers that print character are graphics by spraying very tiny drops on ink directly on to
paper. The print quality of these printers is much better as compared to DMPs. The typical
print quality of these printers is from 300 dots per inch (DPI) to 720 DPI. These printers also
print color.
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Laser printer are also being commonly used with a high – end PCs; particularly those used for
Desk-Top Publishing (DTP). The laser printers provides very high quality printout; typically
in the range of 300 DPI to 2400 DPI. The typical printing speed of laser printers is between 3
to 12 pages per minute.
A printer interface links the printer with the computer. Commands and data from the
computer are sent to the printer the through this interface. The printer produces character on
the paper. One situation in which the printed output ( known as hard copy ) is required when
the output produced at a distance from the user and may be at an undefined or inconvenient
time as an off-line batch processing system. Such the printing required a high-speed printing
in a large quantities and a typically employ a line printer.
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TYPES OF PRINTER
1. Impact Printer
2. Non Impact Printer
PRINTER FUNCTION:
The printer receives the data from the computer and print the data form the computer.
Printer also receives the control character from the computer.
Control characters are not printable character. They will use to send some sort of
control information to the printer.
Some high quality printers are also printing any types of image on the paper; also they
can print the cards and such type of graphical pages.
Widely used control characters are :
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The compact disk used in a Pc similar in shape and size to the audio CD. The computer CD
can hold about 700 MB of data. The computer CD is used to load computer program and
other data in a hard disk of PC. Most of the new computer programs are now only available
on CDs. Some times the programs are directly run form the CD. Also, sometimes the PC may
directly read the data store on the CD at the time of running a program.
Most of the CDs are read only type. That is, the CPU can information store on a CD,
However it cannot store any information on CD. Moreover, most of the CD drives used in the
PC do not have the capability to store the information on CDs. However, writable CDs are
available. Therefore, if a PC has a CD Drive that has witting capability you can store the
information on a writable CD so normally the CD drives works as a input device but it can
also act as an input / output (I/O) device.
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Chapter 4
What Is
Hardware
&
Software?
HARDWARE
E.I.T.L-(ELECON)
There are many physical devices, such as the monitor, floppy disk drive, hard disk drive,
keyboard, printers etc. in your PC. These physical devices are called Hardware. The
hardware does all operation in your PC, such as accepting and storing data, performing
calculations and displaying or printing result.
The various physical devices or the hardware in the PC cannot work on their own. To make
the hardware work, you required a set of programs. A set of program associated with the
operation of a computer is called Software. Different Types of software ( Also called
software programs ) are used on PCs. Software can be classified in to following major
categories :
Operation System. E.g. DOS, Windows 98, Windows XP, UNIX, Linux etc.
Programming languages, such as Basic, FORTRAN, COBOL, C++ etc.
Application programs / packages, such as word processors, spreadsheet, database
Management System (DBMS), etc.
Other application programs doing a specific job, such as accounting payrolls, billing,
Weather forecasting, ticket reservation, etc.
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Chapter 5
Memory
HARDWARE
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MEMORY
Memory is classified into two types:
Primary Memory
Secondary Memory
PRIMARY MEMORY
It is called the main memory or the central memory. It is of two types – RAM and ROM.
RAM is essentially a read / writes memory. Information can be written into and read from
RAM. It is volatile in nature. i.e. It retains the stored information as long as power supply is
not switch off. It is usually sold and installed to the standard adding board called a Single In-
Line Memory Module or SIMM. Ram can be bought separately in case you want to expand
the primary memory of your computer.
Dynamic
Static
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DDR SDRAM
Fig.
(DDR memory (front and back shown)
Has 184 pins and one notch)
With data being transferred 8 bytes at a time DDR RAM gives a transfer rate of (memory bus
clock rate) × 2 (for dual rate) × 8 (number of bytes transferred). Thus with a bus frequency
of 100 MHz DDR – SDRAM gives a max transfer rate of 1600 MB/s.
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SDR SDRAM:
SDR SDRAM is Single Data Rate synchronous dynamic random access memory, a type of
computer memory. The term is used to contrast with Double Data Rate SDRAM, or DDR
SDRAM, but since single data rate SDRAM was the only sort available when SDRAM was
introduced, is simply called "SDRAM", rather than "SDR SDRAM".
SDRAM has a synchronous interface, meaning that it waits for a clock pulse before
responding to its control inputs- it synchonizes with the computer's system bus, and thus with
the processor.
SDRAM has a synchronous interface, meaning that it waits for a clock pulse before
responding to its control inputs- it synchonizes with the computer's system bus, and thus with
the processor.
Currently, 168-pin SDRAM type is not used in new PC systems, and PCs come with DDR or
DDR2 SDRAM, with DDR2 quickly phasing out DDR.
Rambus DRAM
Short for Rambus DRAM, a type of memory (DRAM) developed by Rambus, Inc. Whereas
the fastest current memory technologies used by PCs (SDRAM) can deliver data at a
maximum speed of about 100 MHz, RDRAM transfers data at up to 800 MHz.
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RDRAM is already being used in place of VRAM in some graphics accelerator boards. As of
late 1999, Intel has been using RDRAM in its Pentium III Xenon processors and more
recently in its Pentium 4 processors. Intel and Rambus are also working a new version of
RDRAM, called nDRAM that will support data transfer speeds at up to 1,600 MHz.
ROM is permanent type of memory. Its contents are not lost when the power supplied is not
switch off. Data is hard wired on to these chips at the time of manufacture. They cannot be
change by the user.
While both RAM and ROM are storage devices and can be access randomly, they differ in
that data can be written onto RAM while ROM does not permit the user to write onto it.
ROM retains the data in it even the absence of power and is thus non-volatile storage.
Though data is hardwired, the user is able to program the following types of ROM
SECONDARY MEMORY
The secondary memory is found outside the CPU box and hence sometimes called the
external memory of the external storage. Examples of secondary storage devices include
floppies disks, tapes, cartridges, compact discs, etc.
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The power supply unit checks the quality of the power supply and ensures that the right
amount of power gets supplied to the various parts.
A power supply is the heart of computer system. As human being need proper circulation of
the blood for human body to stay as live, a computer needs a well regulated 5 V and 12 V
DC. Power supply for the proper functioning of its various parts. These DC powers are
supplied by the power supply to the computers. As the power from mains is 240 V AC, with
lots of interface, I cannot be directly fed to computer. So the power supply is used to the
computer and mains to convert 240 V AC to current to well regulated 12 V and 5 V DC
current. Usually hard disk is used 12 V Supply.
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Chapter 6
HARDWARE
E.I.T.L-(ELECON)
In SMPS the O / P is not regulated the continuously but switch on and off at a relatively high
frequency results in similar size transfer and filter capacitor. The input DC is chopped and
high frequency (10 KHZ to 400 KHZ) using and active device and converter transfer the
transfer high frequency wave form are rectify and filtered. A portion of output voltage is used
as a feedback signal for drive circuit for regulator.
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WORKING OF SMPS
In SMPS the mains AC supply is first send to filter unit. This switching transistor, which
generates very high frequency square wave pulses. The square pulses given to primary
winding of a SM transfers. These plusses in to voltage at primary winding of transfer which
will generate voltage at the secondary winding.
This secondary voltage is then rectified and filtered to produce the request output. To regulate
the output generate output voltage is send back to switching section. This voltage is ‗ ON ‗
time of switching transistor, which reduces the output voltage. When there is a reduction in
output voltage reverse action will increase the output voltage. The error voltage is then
sending to control circuit, which controls the switching transistor to regulate the output
voltage.
Bridge rectifier and filter circuit produce the DC current of high voltage by giving main
power supply to line filter circuit, which is unregulated DC current. Now this unregulated DC
current is switch at high frequency by switching transistor. Further it is converting in to DC
current pulses.
This power supply works in on the AC signal. This signal is half wave rectified and given tot
the output stage, which user to transistor for amplification.
This 50 C / S amplified signal are given to the primary coil a transfer which generates 25 V
AC at the secondary winding of transfer. This 25 V supply is then give then the oscillator that
uses IC KIA494 to create high frequency then the signal is given to the driver section through
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oscillator section which amplified by transistor used in the section the amplified signal goes
to output section through coupling transfer and then goes to the primary winding of SM
transformer. This transformer works on this signal and generates the necessary supply at
secondary winding of SM transformer.
TECHNICAL SPECIFICATION
+ 12 V 5.5 Amp
- 12 V 0.5 Amp
+ 5 V: It is used by the logic chip in the system board, the disk drive electronic card and the
adapter card that is installed in the dynamic memory chip.
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1. +5V : RED
2. GND : BLACK
3. GND : BLACK
4. + 12 V : YELLOW
To check the power supply and check the voltage at the power good signal. If the
measurement is between 2.4 to 5.4 DC ranges then the power supply is working but if it is
not in this range the system will not run and hence the power supply must be serviced. Also
check the voltages from the motherboard and drive power connecter. Connect black lead of
the millimeter with ground and the other red with any voltage line. Now the red wire is
known to carry + 5 V and the yellow wire is known to carry + 12 V DC. Now while
measuring this voltage can very from 10.8 to 12.9 V in case of yellow wire, while case of red
wire it may from 4.5 V to 5.5 V. if they are within above given range then the power supply
is working properly.
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Chapter 7
Maintaining
A
Computer Hardware
HARDWARE
E.I.T.L-(ELECON)
The parts of the computer that are most likely to get the affected by the repeated use:
THE DISK DRIVES The disk drives need to be cleaned from time to time using the tools
that are available for doing so.
THE PRINTER Printer creates a lots of paper dust. This needs to be cleaned once in
every 15 days depending on the usage. If the printer is used very frequently, then it should be
cleaned every week. This cleaning can be done using the thin nozzle of the vacuum cleaner.
Care should be taken in doing this because the printer has delicate parts.
THE HARD DISK The computer should not be switch off when a program is working.
DISKS The computer should be never being switch off without removing the diskette
from the drive. Doing this will cause the data on the disk to be lost or will damage the disk
altogether.
MOUSE The mouse has to be cleaned every month. It is best to use the mouse on a firm
and smooth pad. It becomes very easy to operate it that way.
A computer is also machine. It is also likely to have breakdowns. Sometimes an error may
occur in the machines. This error has to be communicated to the engineer looking after the
machines. To make sure that the right thing is communicated, it makes sense to keep a record
of the exact nature of breakdown. Whenever a computer has problem, the exact message that
it displays should be noted down. The application software that was working that should time
is repairing the computer to have a better understanding of how the breakdown happened in
the first place.
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Chapter 8
Booting
A
Computer
HARDWARE
E.I.T.L-(ELECON)
BOOTING A COMPUTER
When you switch on a computer, it goes through a complex set of the instruction. This it does
tot ensure that all its components are working properly and to warn the user if something goes
wrong. This is the first step of very complicated process called booting. Booting is the term
derived from the word bootstrap. Bootstrap is the process of lifting one self up on its own.
The computer also readies it self for you, therefore this process is called booting. The process
of checking itself is called Power On Self Test or POST.
POST is the first thing the computer does when it switch on. If an error detected during the
POST, it warns the user in the form of some message flashed on the screen accompanied with
the series of beeps.
IMPORTANT If there is no beeps, it is no guarantee, that the hardware if fine,
because there may be some error in that even the POST cannot detect.
The following diagram explained the process that the computer goes through before it comes
ready for the user :
POST
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Next, the ROM searches for the operating system and loads it tots complete the process of
booting. Take a look at the next schematic.
START
After this, the user has to replace the disk and press the ‗ Return ‗ key. If the return key is
press without replacing the disk, the operating system files are searched on the hard disk, the
computer cannot get ready to accept commands form the user. If the files are not found on the
hard disk, they are copied to the RAM and the computer can be used.
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BOOTABLE DISK It is very common and convenient to have the operating system files on
the hard disk. However, sometimes due to some error the hard disk does not get ready. This is
why; a backup of the operating system files should always be maintained. A floppy
containing the back up of the operating system files called a ‗ bootable disk ‗. A bootable disk
allows the computer‘s operating system to get loaded. At least two bootable disks prepare and
maintained.
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Chapter 9
Basic Trouble
Shooting
HARDWARE
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Press the Ctrl key, the Alt key and the Delete key at the same time
You may need to repeat this 2 or 3 times before you get a dialog box that asks if you
want to End Task, Shutdown or Cancel. Choose to End Task
Try to Shutdown your computer again.
If your computer will still not shutdown, repeat the task again.
Perhaps a key on the keyboard is stuck. Check to make sure the mouse and keyboard
Plugs are properly connected in the back of the computer.
Make sure the monitor is on by checking for a green light on the bottom, front. Also,
make sure the monitor cable is plugged in correctly on the back of the computer.
Check that power cord is plugged in.
Shutdown two computers one with non-working monitor and one with working
monitor.
Disconnect the monitors and connect them to the opposite computer.
Reboot both computers.
This should help you to determine if the monitor is not working or the video card on the
computer is not working properly.
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MY COMPUTER IS “FROZEN”
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An Internet cable is connected to your computer/laptop and is plugged into to the wall
drop (looks like a phone jack).
The Internet cable is free of kinks and the end connector is securely fastened.
The icon ―plug‖, located on the bottom left corner of your screen is connected.
If not, left click on it to connect to the Internet.
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BE SURE TO :
First connect the VGA cord from the projector to the laptop.
Turn on the projector.
Boot ups the laptop.
On the laptop, press keys Fn (on the bottom left) and F5 (top row) at the same time.
You may need to do this several times to have images on both the laptop screen and the
projected surface.
Or "Press the Mode button on the top of the projector so it will ―recognize‖ the
computer connection.
May need to press the Mode button several times.
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Turn on printer
Boot up computer that is connected to printer
Boot up all other computers on network
If the connected computer was not booted up before turning on the printer, shut it down.
If you are trying to print from a network computer not connected to the printer.
You will still need to make sure that the above sequence is followed before sending
your file to the printer.
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Chapter 11
Introduction
NETWORKING
E.I.T.L-(ELECON)
Introduction
A LAN is a high-speed data network that covers a relatively small geographic area.
LANs offer computer users many advantages, including shared access to devices and
applications, file exchange between connected users, and communication between
users via electronic mail and other applications.
LAN protocols function at the lowest two layers of the OSI reference mode.
LAN topologies define the manner in which network devices are organized. Four
common LAN topologies exist: bus, ring, star, and tree.
These topologies are logical architectures, but the actual devices need not be
physically organized in these configurations.
Logical bus and ring topologies, for example, are commonly organized physically as a
star.
Devices commonly used in LANs include repeaters, hubs, LAN extenders, bridges,
LAN switches, and routers.
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Chapter 12
Networking Basics
NETWORKING
E.I.T.L-(ELECON)
NETWORKING BASICS
When networks first came into being, computers could typically communicate only with
computers from the same manufacturer. For example, companies ran either a complete
DEC net solution or an IBM solution—not both together.
In the late 1970s, the OSI (Open Systems Interconnection) model was created by the
International Organization for Standardization (ISO) to break this barrier. The OSI model
was meant to help vendors create interoperable network devices. Like world peace, it‘ll
probably never happen completely, but it‘s still a great goal.
The OSI model is the primary architectural model for networks. It describes how data and
network information are communicated from applications on one computer, through the
network media, to an application on another computer.
The OSI reference model was created in the late 1970s to help facilitate data transfer
between network nodes.
One of the greatest functions of the OSI specifications is to assist in data transfer between
disparate hosts.
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This means you can transfer data between a Unix host and a PC, for example. The OSI is
not physical; rather, it is a set of guidelines that application developers can use to create
and implement applications that run on a network.
The OSI has seven different layers, which are divided into two groups.
The top three layers define how the applications within the end stations will communicate
with each other and with users.
The bottom four layers define how data is transmitted end-to-end. Figure 2.1 shows the
three upper layers and their functions, and Figure 2.2 shows the four lower layers and
their functions.
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In Figure 2.1, you can see that the user interfaces with the computer at the application
layer, and also that the upper layers are responsible for applications communicating
between hosts. Remember that none of the upper layers know anything about networking
or network addresses. That is the responsibility of the four bottom layers, which are
shown in Figure 2.2.
The four bottom layers define how data is transferred through a physical wire or through
switches and routers, and how to rebuild a data stream from a transmitting host to a
destination host‘s application.
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The Application layer of the OSI model is where users communicate to the computer.
The Application layer is responsible for identifying and establishing the availability of
the intended communication partner and determining if sufficient resources for the
intended communication exist.
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The Presentation layer gets its name from its purpose: It presents data to the
Application layer.
Computers are configured to receive this generically formatted data and then convert
the data back into its native format for actual reading (for example, EBCDIC to
ASCII). By providing translation services, the Presentation layer ensures that data
transferred from the Application layer of one system can be read by the Application
layer of another host.
The OSI has protocol standards that define how standard data should be formatted.
TIFF The Tagged Image File Format is a standard graphics format for high-
resolution, bitmapped images.
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JPEG The Joint Photographic Experts Group brings these photo stand- darts
to us.
MIDI The Musical Instrument Digital Interface is used for digitized music.
MPEG The Moving Picture Experts Group‘s standard for the compression and
coding of motion video for CDs is increasingly popular. It pro- vides
digital storage and bit rates up to 1.5Mbps.
The Session layer is responsible for setting up, managing, and then tearing down
sessions between Presentation layer entities.
The Session layer also provides dialog control between devices, or nodes.
The Session layer basically keeps different applications‘ data separate from other
applications‘ data.
The following are some examples of Session-layer protocols and inter- faces (according to
Cisco):
Network File System (NFS) Was developed by Sun Microsystems and used with
TCP/IP and Unix workstations to allow transparent access to remote resources.
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Structured Query Language (SQL) Was developed by IBM to provide users with a
simpler way to define their information requirements on both local and remote
systems.
Remote Procedure Call (RPC) Is a broad client/server redirection tool used for
disparate service environments. Its procedures are created on clients and performed on
servers.
Services located in the Transport layer both segment and reassemble data from upper-
layer applications and unite it onto the same data stream.
They provide end-to-end data transport services and can establish a logical connection
between the sending host and destination host on an internetwork.
Some of you might already be familiar with TCP and UDP and know that TCP is a
reliable service and UDP is not.
Application developers have their choice of the two protocols when working with
TCP/IP protocols.
The Transport layer is responsible for providing mechanisms for multiplexing upper-
layer application, session establishment, and teardown of virtual circuits.
It also hides details of any network-dependent information from the higher layers by
providing transparent data transfer.
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Flow Control
Data integrity is ensured at the Transport layer by maintaining flow control
and allowing users the option of requesting reliable data transport between
systems. Flow control prevents a sending host on one side of the connection
from overflowing the buffers in the receiving host—an event that can result in
lost data. Reliable data transport employs a connection-oriented
communications session between systems, and the protocols involved ensure
the following will be achieved:
The segments delivered are acknowledged back to the sender upon their
reception.
Segments are sequenced back into their proper order upon arrival at their
destination.
The Network layer is responsible for routing through an internetwork and for network
addressing. This means that the Network layer is responsible for transporting traffic
between devices that are not locally attached. Routers, or other layer-3 devices, are
specified at the Network layer and provide the routing services in an internetwork.
Once an exit interface is chosen, the packet will be sent to the interface to be framed
and sent out on the local network.
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If the entry for the destination network is not found in the routing table, the router
drops the packet.
Two types of packets are used at the network layer: data and route updates.
Data packets Are used to transport user data through the internetwork, and
protocols used to support data traffic are called routed protocols. Examples of
routed protocols are IP and IPX.
Route update packets Are used to update neighbor routers about net- works
connected to routers in the internetwork. Protocols that send route update
packets are called routing protocols and examples are RIP, EIGRP, and OSPF,
to name a few. Routing update packets are used to help build and maintain
routing tables on each router.
The Data Link layer ensures that messages are delivered to the proper device and
translates messages from the Network layer into bits for the Physical layer to transmit.
It formats the message into data frames and adds a customized header containing the
hardware destination and source address.
This added information forms a sort of capsule that surrounds the original message in
much the same way that engines, navigational devices, and other tools were attached
to the lunar modules of the Apollo project.
These various pieces of equipment were useful only during certain stages of space
flight and were stripped off the module and discarded when their designated stage was
complete.
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Data traveling through networks is similar. Figure shows the Data Link layer with the
Ethernet and IEEE specifications. Notice in the figure that the IEEE 802.2 standard is
used in conjunction with the other IEEE standards, adding functionality to the existing
IEEE standards.
You need to understand that routers, which work at the Network layer, do not care
about where a host is located but only where networks are located.
They also keep track of the best way to get to a remote network.
The Data Link layer is responsible for uniquely identifying each device on a local
network.
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Some use audio tones, while others employ state transitions— changes in voltage
from high to low and low to high. Specific protocols are needed for each type of media to
describe the proper bit patterns to be used, how data is encoded into media signals, and the
various qualities of the physical media‘s attachment interface.
The Physical layer specifications specify the electrical, mechanical, procedural, and
functional requirements for activating, maintaining, and deactivating a physical link between
end systems.
At the Physical layer, the interface between the Data Terminal Equipment, or DTE,
and the Data Circuit-Terminating Equipment, or DCE, is identified. The DCE is usually
located at the service provider, while the DTE is the attached device. The services available
to the DTE are most often accessed via a modem or Channel Service Unit/Data Service Unit
(CSU/DSU).
The Physical layer‘s connectors and different physical topologies are defined by the
OSI as standards, allowing disparate systems to communicate. The CCNA course and exam
are only interested in the Ethernet standards.
The Department of Defense (DoD) model is a condensed version of the OSI model. It is
comprised of four, instead of seven, layers:
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Figure 2.5 shows a comparison of the DoD model and the OSI reference model. As you
can see, the two are similar in concept, but each has a different number of layers with
different names.
The Host-to-Host layer parallels the functions of the OSI‘s Transport layer, defining
protocols for setting up the level of transmission service for applications. It tackles
issues like creating reliable end-to-end communication
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In simple terms, a protocol is an agreed set of rules that determine how something will
operate.
A routing protocol is a set of rules that describes how Layer 3 routing devices will
send updates between each other about the available networks. If more than one path
to the remote network exists, the protocol also determines how the best path or route
is selected.
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A routing protocol is the mechanism used to update the Layer 3 routing devices.
When they all have the same accurate understanding of the network, they can route
the data across the best path.
Participating routers advertise the routes that they know about to their neighbors in
routing updates. Routes learned from routing updates are held in the routing table.
It is important to distinguish between the datagram and the routing protocol used to
determine the path of the datagram.
The routed protocol is the Layer 3 protocol used to transfer data from one end device
to another across the network. The routed protocol is the Layer 3 datagram that carries
the application data as well as the upper-layer information.
The routing protocol is the protocol used to send updates between the routers about
the networks that exist in the organization, thereby allowing the routing process to
determine the path of the datagram across the network.
The metric is a value that is assigned to each path based on the criteria specified in the
routing protocol. The Metric field is used to determine which path to use if there are
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multiple paths to the remote network. The metric used depends on the routing
protocol.
This value is used to choose between different paths to the same destination network,
to select the best path. If the values are the same, either the router selects the path that
it heard first, or it uses both paths, sending the datagrams across each route.
It is the responsibility of the end device to reassemble the datagrams before sending
them to the application.
Although the switching and routing functions within the router are set, there are many
differences to be seen among the different routing protocols.
The routing protocols are essentially applications on the router. Their purpose is to
ensure the correct and timely exchange of information about the network between the
routers so that the routers can successfully perform the routing and switching
functions described previously.
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IP routing protocols can be divided into several distinct groups. The first is the
difference between protocols that send the mask in the updates and the older protocols
that do not. These are labeled classless and classful protocols, respectively.
Classful routing protocols do not carry the subnet or routing mask in the update. The
older distance vector protocols tend to be classful. This incapability to carry the
subnetting information leads to design constraints in the IP network.
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Router interfaces within the same network can have different subnet
masks (VLSM).
Some of the classless routing protocols, including BGP-4 and RIP v2,
support the use of classless interdomain routing (CIDR).
Some routes can be summarized within the major NIC number. This is
done manually.
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In a layer-2 switched network, the network is flat. Every broadcast packet transmitted
is seen by every device on the network, regardless of whether the device needs to
receive the data.
Because layer-2 switching creates individual collision domain segments for each
device plugged into the switch, the Ethernet distance constraints are lifted, which
means larger networks can be built. The larger the number of users and devices, the
more broadcasts and packets each device must handle.
Another problem with a flat layer-2 network is security, as all users can see all
devices. You cannot stop devices from broadcasting and users trying to respond to
broadcasts.
Your security is passwords on the servers and other devices. By creating VLANs, you
can solve many of the problems associated with layer-2 switching.
1. Broadcast Control
2. Security.
3. Flexibility & Scalability.
VLANs are typically created by an administrator, who then assigns switch ports to the
VLAN. These are called static VLANs. If the administrator wants to do a little more work
up front and assign all the host devices‘ hardware addresses into a database, the switches
can be configured to assign VLANs dynamically.
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Static VLANs
Static VLANs are the typical way of creating VLANs and the most secure.
The switch port that you assign a VLAN association always maintains that association
until an administrator changes the port assignment.
This type of VLAN configuration is easy to set up and monitor, working well in a net-
work where the movement of users within the network is controlled. Using network
management software to configure the ports can be helpful but is not mandatory.
Dynamic VLANs
Cisco administrators can use the VLAN Management Policy Server (VMPS) service to
set up a database of MAC addresses that can be used for dynamic addressing of VLANs.
VMPS is a MAC address–to–VLAN map- ping database.
The first kind of access list is the standard access list, used to build policy sets of IP
addresses or IP networks. In describing the standard access list, we will examine the
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basic syntax used in all Cisco access lists, including the basic permit/deny operation
for including or excluding network objects from a policy set, address specification
and masking, and the sequence used in processing access lists. The standard access
list cannot cover all the policies we may wish to specify, particularly when we want to
do packet filtering.
This leads us to the second type of access list: the extended access list. This kind of
list extends the format of the standard access list to specify packet filtering policies.
Once we have learned to build the basic access list types, the chapter covers how to
optimize, build, and maintain access lists.
Once policy sets are defined with standard access lists, the access list can restrict
access to network resources, determine which routes are accepted and distributed,
and change routing metrics to influence traffic behavior.
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We defined Policy Set #1, consisting of the hosts allowed to log into the router, as
follows:
How does this policy set map to actual access lists? Here is the mapping:
Router logins: Only from hosts with IP addresses defined in Policy Set #1
line vty 0 4
access-class 1 in
One type of access list is designed to build policy sets for that type of control: the
extended access list.
This kind of access list extends the standard access list to include the ability to
specify protocol type, protocol port, and destination in a certain direction. Of our
three key motivations for building access policies, the main motivation for using
extended access lists is security.
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It is often used for firewall purposes—specifying the packets that can pass through
a router between networks of various degrees of trust. Thus, we'll speak in terms
of allowing or denying packets through a router in our discussions of matching
extended access lists.
To implement a policy allowing only web packets to the web server, we need to
define a policy set that includes only packets for web protocols. The policy set
specification looks like this:
How does this map into an extended access list? Here is the translation:
interface Ethernet 0
ip access-group 101 out
Thus with the use of standard and extended access control list we can apply different
kinds of security features to the router.
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Chapter 13
Designing Of
Ethernet Network
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o Type of Network
o Main Access points.
o Type of Network Media.
o Type of protocols to be used as per applications.
o Type of Security features to be added.
o No. of users to access Internet Traffic.
o Type of routing parameters to be used.
o And many other…
3.2 Requirements:
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3.3 Implementation:
Here we have all the designing policies & the requirements now we have to start designing
the network.
Now all the 12 routers are well separated from each other so we are supposed to
use fiber links rather than serial link to connect the routers.
3 manufacturing units are controlled by SAP server so the link between SAP and
the manufacturing unit must not be broken.
So, all the manufacturing units and Purchase department is directly connected to
the SAP department.
Also all the departments are connected in a ring topology so if one of the links
breaks than also the communication between all the departments can be possible.
Corporate Offices are directly connected to the N/W department so that client
from corporate office can access the internet and all the data with higher b/w and
easily.
Here Manufacturing units are not provided enough privileges to access the
internet.
Other departments like Engineering and R&D are not provided all time internet
facility, they are provided their time slots in which they can access internet, and
this feature enhances b/w utilization.
This is big firm and the future expansion may take place in the campus, so keep
this idea in mind we have used EIGRP as a routing protocol.
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We also have only 10 global IPs provided by ISP for the internet access.
So, we have used NAT (Network Address Translation) for the internet access for
all the departments in the N/W router from where campus is connected to the
outside world.
In the access control list of all the routers we have also provided that no other than
N/W department can log on to router and cant establish a telnet session.
All the Departments are connected with intranet and they can communicate
through it.
Now, Finance and Marketing department is sharing the same building so they are
given connections from a single router.
But in this case if broadcast takes place than all the pcs and other devices will be
affected.
So, for the precaution VLAN has been created in the switch of the Finance &
Marketing Dept. Router.
Vlan prevents the broadcast packets to flow from vlan1 to vlan2 and vice-versa.
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If and only if server shares the network printer to that pc than only client can
access the printer.
That‘s how all the policies for the implementation get defined.
Now on the simulator first we have implement whole topology and than the actual
implementation on the physical devices done.
It is a user friendly simulator to work with and also it‘s freely available. There is
no license cost for the same.
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Chapter 14
Simulation
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SIMULATION
Here in a simulation part first we have make the whole virtual topology in the packet
tracer and then start the implementing the different polices and configuring the different
n/w devices.
Here we have used 12 routers for the 12 departments and uses same no of switches to
connect the end devices to the router.
For the simplicity we have put in 5 pcs and a printer in a single department, actual n/w
vary from this.
We have connected all the routers by fiber optic cable with other routers.
The end devices are connected to switch using straight through utp cat-5 cable. And the
switches are also connected to the router with the same.
When the all physical connections are made the configuration of devices starts.
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4.1 Routing:
Bandwidth, Delay, Load, Reliability, MTU are the metric parameters for the EIGRP
to count the distance between hopes.
For using EIGRP we have put whole system in a single autonomous system.
We have created the access lists in the each and every router to provide some
privileges and to put some restrictions in access the n/w resources.
Here we have use only extended access list rather than standard access list to provide
more filtering features.
With the help of access lists telnet session for the normal user has been restricted.
Here are the router configurations for all the routers have been displayed.
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Chapter 15
Conclusion
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CONCLUSION
By designing such a complex topology we came to know many things such as,
To communicate between far situated two different stations fiber is more reliable than
serial communication.
In a real network where expansion is not known for routing purpose IGRP or EIGRP is
preferable.
When you have two different departments in the same place than you can use switch and
can create VLANs rather than using a Router for the same purpose. VLANs can solve the
problem of broadcasting.
For communication between outside world ( e.g. Internet ) you have limited public IPs for
your many private IPs. So you can use NAT or PAT for internet access for the whole
internal network.
IGRP & EIGRP are the Cisco property protocols so if one want to use them. There must
be Cisco devices at both ends.
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Chapter 15
Bibliography
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BIBLIOGRAPHY
SOFTWARE
Packet Tracer 4.0..
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Notes
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Notes
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Thanking You