100% ASSURED PLACEMENT FOR HARDWARE AND NETWORKING PAY PLACEMENT FEES AFTER GETTING PLACEMENT.
IICT Chromepet, Chennai provides real-time and placement focused computer networking training in chennai . Our hardware and networking course includes basic to advanced level and our computer networking course is designed to get the placement in good MNC companies in chennai as quickly as once you complete the networking LAN, WAN training course. Our computer networking trainer is hardware and networking certified expert and experienced working professionals with hands on real time multiple Networking projects knowledge. We have designed our computer networking course content and syllabus based on students requirement to achieve everyone's career goal. In our computer networking training program, you will learn Networking Basics, Wired Networking concepts, Local Area Network, WAN, Wireless Networking, Network Security, networking access control, troubleshooting, computer networking real time project and hardware and networking placement training.
• Computers are machines that perform tasks or calculations
according to a set of instructions, or programs. The first fully
electronic computers, introduced in the 1940s, were huge
machines that required teams of people to operate.
• Compared to those early machines, today's computers are
amazing. Not only are they thousands of times faster, they can
fit on your desk, on your lap, or even in your pocket.
What is a Computer?
• Computer is a electronic digital data processing device which
process the data at very high speed and also stores the data
for future use.
• Almost all other electronic devices handles single task
• Computer is simply all in one electronic data processing
• Classifications of Computers
– Super Computer
– Mainframe Computer
– Mini Computer
– Micro Computer
• Classifications of PC’s
– PC – XT
– PC – AT
– PC - ATX
• PC Hardware & Software
– Hardware - Study of physical parts & components
of a computer
– Software - Software is collection of programs,
instructions arranged in a sequential manner to
carry out some specified tasks.
• Computers work through an interaction of hardware and
software. Hardware refers to the parts of a computer that you
can see and touch, including the case and everything inside it.
• The most important piece of hardware is a tiny rectangular
chip inside your computer called the central processing unit
(CPU), or microprocessor. It's the "brain" of your computer—
the part that translates instructions and performs
• Hardware items such as your monitor, keyboard, mouse,
printer, and other components are often called hardware
devices, or devices.
Languages Used in Computers
• Machine Level Languages – MLL
• Assembly Language – Assembler
• High Level Language – HLL
Number systems used in Computer
• Binary Number Systems
• Octal Number Systems
• Hexa - decimal Number Systems
• BCD - Binary Coded Decimal
• ASCII – American Standard Code for Information Interchange
• EBCDIC – Extended Binary Coded Decimal Interchange Code
•A motherboard is a multi-layered printed circuit board. Copper
circuit paths called tracks that resemble a complicated roadmap
carry signals and voltages across the motherboard.
• A typical motherboard provides attachment points for one or
more of the following: CPU, graphics card, sound card, hard disk
controller, memory (RAM), and external peripheral devices.
•It contains the chipset, which controls the operation of the CPU,
the PCI, ISA, AGP, and PCI Express expansion slots, and (usually)
the IDE/ATA controller
What is a Port?
• In computer hardware, a 'port' serves as an interface between
the computer and other computers or peripheral devices.
• Physically, a port is a specialized outlet on a piece of
equipment to which a plug or cable connects. Electronically,
the several conductors making up the outlet provide a signal
transfer between devices.
• The term 'port' is derived from a latin word 'porta' (gate,
• A software port (usually just called a 'port') is a virtual/logical
data connection that can be used by programs to exchange
• The most common of these are TCP and UDP ports, which are
used to exchange data between computers on the Internet.
• Serial Port
• Parallel Port
• Game Port
• PS/2 Port
• USB Port
• Audio Ports
Data Transfer• Serial Data Transfer
• Parallel Data Transfer
• In telecommunication and computer science, serial
communication is the process of sending data one bit at a
time, sequentially, over a communication channel or
computer bus. This is in contrast to parallel communication,
where several bits are sent together, on a link with several
• Serial computer buses are becoming more common even at
shorter distances, as improved signal integrity and
transmission speeds in newer serial technologies have begun
to outweigh the parallel bus's.
USB• Universal Serial Bus
• USB (Universal Serial Bus) is a specification to establish
communication between devices and a host controller
(usually personal computers), developed and invented Intel.
USB is intended to replace many varieties of serial and parallel
• USB can connect computer peripherals such as mice,
keyboards, digital cameras, printers, personal media players,
flash drives, and external hard drives. For many of those
devices, USB has become the standard connection method.
• USB version 1.0 = 12 Mbps
• USB version 2.0 = 480 Mbps
• Supports 127 Devices
• Hot swappable
• Plug and Play
• USB (Universal Serial Bus) is a new technology intended
to replace the current dedicated ports used for
keyboards and mice.
• The USB interface is specifically designed to allow easy
connection of a wide variety of devices; it is intended
to be user-friendly and truly "plug and play".
• On a system equipped with USB, one can "hot swap"
devices, meaning they can be plugged into the system
or removed without needing to power the system down
or doing anything to it before the change is made.
Fire Wire 1394
• The IEEE 1394 interface is a serial bus interface standard for
high-speed communications and real-time data transfer,
frequently used by personal computers, as well as in digital
audio, digital video, automotive, and aeronautics applications.
• Fire Wire can connect up to 63 peripheral devices using tree
• Supports plug and play.
• Hot swapping supported i.e. no need to switch off the system
to connect/disconnect devices.
• Cables can be 4.5 meters long and flexible than other parallel
ISA - Industry Standard Architecture
• Stands for "Industry Standard Architecture." ISA is a type of
bus used in PCs for adding expansion cards. For example, an
ISA slot may be used to add a video card, a network card, or
an extra serial port.
• The original 8-bit version of PCI uses a 62 pin connection and
supports clock speeds of 8 and 33 MHz. 16-bit PCI uses 98
pins and supports the same clock speeds.
• Accelerated Graphics
Port is an interface
specification that enables
3D graphics to display
quickly on ordinary
• AGP is designed to
convey 3-D images (for
example, from Web sites
or CD-ROMs) much more
quickly and smoothly than
is possible today on any
system other than a
• PCI (Peripheral Component Interconnect) is an inter connection system
between a microprocessor and attached devices in which expansion slots are
spaced closely for high speed operation. PCI transmits 32 bits at a time in a
124-pin connection (the extra pins are for power supply and grounding) and
64 bits in a 188-pin connection in an expanded implementation
• Computer memory refers to units or devices that are used to
store data or programs (sequences of instructions) on a
temporary or permanent basis for use in an electronic digital
• Although memory is technically any form of electronic
storage, it is used most often to identify fast, temporary
forms of storage.
RAM & ROM
• RAM (random access
memory) chips hold the
program and data that the
CPU is presently
RAM is called temporary
because as soon as the
computer is turned off,
everything in RAM is lost.
RAM storage is
frequently expressed in
megabytes. Thus, a
computer with 64MB RAM
has memory that hold
about 64 million
characters of data and
ROM (read only memory) chips
have programs built into them
at the factory. Unlike RAM
chips, the contents of ROM
chips cannot be changed user.
ROM chips typically contain
special instructions for
detailed computer operations.
For example, ROM instructions
the computer, give keyboard
keys their special control
capabilities, and put
characters on the screen.
READ ONLY MEMORY (ROM)
Random Access Memory (RAM)
• SRAM DRAM
• FPM EDO RAM
• SDRAM DDRSDRAM
• DDR2SDRAM DDR3SDRAM
• EDO DRAM, sometimes referred to as Hyper Page Mode
enabled DRAM, is similar to Fast Page Mode DRAM with the
additional feature that a new access cycle can be started
while keeping the data output of the previous cycle active.
• This allows a certain amount of overlap in operation
(pipelining), allowing somewhat improved performance. It
was 5% faster than Fast Page Mode DRAM.
128MB 100Mhz SDRAM DIMM
• Pictured here is the 128 megabyte (MB) 100 megahertz (MHz) SDRAM
un-buffered DIMM. This product is available for both Workstations
• A DIMM (dual in-line memory module) is a double SIMM. Like a SIMM,
it's a module containing one or several RAM chips on a small circuit
board with pins that connect it to the computer motherboard. For
SDRAM chips, which have a 64 data bit connection to the computer,
SIMMs must be installed in in-line pairs (since each supports a 32 bit
path). A single DIMM can be used instead. A DIMM has a 168-pin
connector and supports 64-bit data transfer.
5000584 MEM DDR 512MB PC266B 32X8 R0
• The 512-megabyte (MB) Double Data Rate-Synchronous DRAM
(DDR-SDRAM) module supports data transfers on both edges of
each clock cycle, effectively doubling the memory chip's data
throughput. DDR-SDRAM is also called SDRAM II. DDR SDRAM
(double data rate SDRAM) is synchronous dynamic RAM
(SDRAM) that can theoretically improve memoryclock speed to
at least 200 MHz*. It activates output on both the rising and
falling edge of the system clock rather than on just the rising
edge, potentially doubling output.
• DDR2 SDRAM is a double data rate synchronous dynamic
random access memory interface. In addition to double
pumping the data bus as in DDR SDRAM (transferring data on
the rising and falling edges of the bus clock signal), DDR2
allows higher bus speed and requires lower power.
• The two factors combine to require a total of 4 data transfers
per internal clock cycle.
• In addition DDR2-SDRAM offers new features and functions
that enable higher a clock rate and data rate operations of
400 MHz, 533 MHz, 667 MHz, and above.
• DDR2 transfers 64 bits of data twice every clock cycle. DDR2-
SDRAM memory is not compatible with current DDR-SDRAM
• DDR3 SDRAM is an improvement over its predecessor, DDR2
SDRAM, and the two are not compatible. The primary benefit
of DDR3 is the ability to transfer at twice the data rate of
• With data being transferred 64 bits at a time per memory
module, DDR3 SDRAM gives a transfer rate of, with a
memory clock frequency of 100 MHz, data transfer rate of
• A DIMM (dual in-line memory module) is a double SIMM (single in-
line memory module). Like a SIMM, it's a module containing one or
several random access memory(RAM) chips on a small circuit board
with pins that connect it to the computer motherboard.
• A SIMM typically has a 32 data bit path to the computer that
requires a 72-pin connector. For synchronous dynamic RAM (SDRAM)
chips, which have a 64 data bit connection to the computer, SIMMs
must be installed in in-line pairs (since each supports a 32 bit path).
A single DIMM can be used. A DIMM has a 168-pin connector and
supports 64-bit data transfer.
• This is where the floppy disk drive cable connects to
the motherboard. Pin 1 orientation is indicated in
the graphic. The slot is keyed and only accepts a
keyed cable in the proper orientation
Panasonic 1.44MB Floppy Disk Drive
The major parts of a FDD include:
Read/Write Heads: Located on both sides of a diskette, they move
together on the same assembly
Drive Motor: A very small spindle motor engages the metal hub at the
center of the diskette, spinning it at either 300 or 360 rotations per
Stepper Motor: This motor makes a precise number of stepped
revolutions to move the read/write head assembly to the proper track
position. The read/write head assembly is fastened to the stepper
Mechanical Frame: A system of levers that opens the little protective
window on the diskette to allow the read/write heads to touch the
dual-sided diskette media
•The cable end that has a split and twist in it connects to the floppy
disk drive. The bottom pin connector gets attached to the
motherboard's floppy disk controller.
• The ribbon cable contains a red dotted edge which aligns with pin
one. It can be identified by the silk-screened markings on the
motherboard and it is normally the end closest the rear edge of the
Storing the Data• Data is stored on the surface of a
platter in sectors and tracks. Tracks
are concentric circles, and Sectors are
pie-shaped wedges on a tracks.
• A typical Track is shown in yellow; a
Sector is shown in blue. A sector
contains a fixed number of bytes – 512
bytes. Sectors are not read individually
on most PCs; they are grouped
together into continuous chunks called
• A typical job, such as loading a file
into a spreadsheet program, can involve
thousands or even millions of individual
• The process of low-level formatting a
drive establishes the tracks and
sectors on the platter. The starting
and ending points of each sector are
written onto the platter.
• This process prepares the drive to hold
blocks of bytes. High-level formatting
then writes the file-storage
structures, like the file-allocation
table, into the sectors. This process
prepares the drive to hold files
• Data Recording Technique – Write Pre Compensation
• Access Time
• Latency Time
• Landing Zone
• The serial ATA or SATA computer bus, is a storage-interface for
connecting host bus adapters to mass storage devices such as
hard disk drives and optical drives. The SATA host adapter is
integrated into almost all modern consumer laptop computers
and desktop motherboards.
• SATA offers several compelling advantages over the older
parallel ATA (PATA) interface: reduced cable-bulk and cost
(reduced from 80 wires to seven), faster and more efficient
data transfer, and hot swapping.
• Serial ATA was designed to replace the older ATA (AT
Attachment) standard (also known as EIDE). It is able to use
the same low level commands, but serial ATA host-adapters
and devices communicate via a high-speed serial cable over
two pairs of conductors.
SATA• SATA Revision 1.0 (SATA 1.5Gb/s)
– First-generation SATA interfaces, now known as SATA 1.5
Gbit/s, communicate at a rate of 1.5 Gbit/s.
• SATA Revision 2.0 (SATA 3Gb/s)
– Second-generation SATA doubling maximum data
throughput from 150 MB/s to 300 MB/s.
• SATA Revision 3.0 (SATA 6Gb/s)
– Third-generation SATA doubles the SATA-V2 throughput
300MB/s to 600MB/s or 6Gbps.
• Serial Attached SCSI (SAS) is a computer bus, which moves
data to and from computer storage devices such as hard
drives and tape drives. SAS depends on a point-to-point serial
protocol that replaces the parallel SCSI bus technology that
• SAS offers backwards-compatibility with second-generation
SATA drives. SATA 3 Gbit/s drives may be connected to SAS
backplanes, but SAS drives may not be connected to SATA
• SAS stands for Serial Attached SCSI. Basically, a SAS drive
utilizes the same form factor as a SATA drive but has several
high performance advantages. First of all, there's the platter
speed. While typical SATA drives operate at 7200RPM, a SAS
drive operates at 10K or 15K.
Managing large sets of Data
Prevent failed disks from making data unavailable.
More efficiently balance the I/O load across disks.
Allow file systems to grow while they are in use.
Allow dual-host fail-over configurations with redundant
Techniques for Managing Data:
– Hot Spares
– Disk Striping
– RAID 5
– Disk Mirroring
Common RAID implementations
• RAID 0: Striping
• RAID 1: Mirroring
• RAID 5: Striping with distributed parity
• Multiple physical disks are combined into a single virtual disk
• The address space is contiguous
• There is no data redundancy (less reliable)
• Loss of one number equates to loss of all data
• Min 2 disks to Max 32 Disks
• Allows to grow virtual disk by concatenating additional
physical disk to it
• 100% disk capacity is available
• Best Read / Write Performance (More Controllers)
• No redundancy
• Full redundant copy of data is available on one or more disks
• Slower write performance
• Both drives can be used for reads to improve performance
• 50% disk capacity is only available
• In case of failure, applications can continue to use the
remaining half of the mirror
• Recovering from a disk failure – duplicating the contents of
the failed disk’s mirror into a new drive
• This is the only method which supports OS redundancy.
• RAID 6 Distributed Dual Parity
• Extension of RAID 5
• Providing additional fault tolerance
• Read performance same as RAID 5
• But write performance slow due to dual parity
• Disk usage less compared to RAID 5
• Two disk failures are supported
Backup and Restore
Reasons to take Backup
• Unexpected Hard Disk Failures
• Failures of Support Hardware
• Physical Damage
• Software Problems
• Human Error
• Restore - Whenever there is an unexpected complete failure
of a system, the backed up data to be restored to the specific
system within a short period of time, to continue the
High Availability & Fault Tolerance
• High Availability:
Can provide access to data most of the time while
maintaining the integrity of that data.
In case of failure within few minutes the data will be
• Fault Tolerance:
Provide data integrity and continuous data availability.
Data is available even in case of failure.
GW Sound Card w/ Media Vision Chipset
• A sound card (also referred to as an audio card) is a
peripheral device that attaches to the ISA or PCI Slot on
a motherboard to enable the computer to input, process,
and deliver sound. The sound card's four main functions
are: as a synthesizer (generating sounds), as a MIDI
interface, analog to digital conversion (used,
• for E.g., in recording sound from a microphone), and digital
to analog conversion (used, for E.g., to reproduce sound
for a speaker)..
AGP Graphics Accelerator
• AGP offers high-speed data transfer to and from
RAM, optimizing the use of memory and minimizing
the amount of memory necessary for high-
• The AGP main memory use is dynamic, meaning that
when not being used for accelerated graphics, main
memory is restored for use by the Operating System
or by other applications.
ModemWhat is a Modem ?
Modem takes digital information from computer and
converts it to an analog signal, which is then transmitted
through a phone line.
There are four basic types of modems:
The external and USB set on your desk outside the PC
while internal and built-in are inside the PC
Modem stands for
• Telephone lines were designed
to transmit the human voice,
not electronic data from
computers. Modems were
invented to convert digital
computer signals into a form
that allows them to travel over
• Modems accept digital data supplied
by the local PC, and convert it to a
modulated analog wave form that can
be transmitted over a normal analog
phone line. And conversely, modems
also accept a modulated analog wave
from the telephone line, convert it to
a digital form, and pass it on to the
Modem Line Cable
• This is the cable that ships with the modems
for connection to a telephone jack. The green
coded end fits in the modem Line-in jack. The
clear end connects to a telephone line jack,
usually on a wall.
• Short for Network Interface Card, a NIC is also commonly
referred to as a network adapter and is an expansion card or
an integrated card that enables a computer to connect to a
network such as a home network and/or the Internet using a
Ethernet cable with a RJ-45 connector.
UTP/STP Network Cables
• The Unshielded Twisted Pair (UTP) network
cable is used to save money on a hub when
connecting two computers together with
twisted pair. The RJ45 cable is crossed
over, meaning that when attached to the
machines, the RJ45 connector is crimped
opposite of the other connector. two
computers may connect to one another by
the use of an RJ-45 Crossover cable.
Remote keyboard and mouse kit
• The Destination II® input kit consists of a remote
keyboard, a remote mouse, a remote receiver, and the driver
• The remote receiver is used to transfer the radio frequency
signal from the keyboard and mouse to the computer. On the
graphic, click the hyperlinks for more information. The
receiver must be placed at least 8 inches or 20 centimeters
from any electromechanical device, including the computer,
the computer monitor, and external storage drives.
Cd - Rom Drives
These are the
are given by
Gateway along with
• Cd-drives are only IDE devices.
• CD- rom drives can only read data from the CD’s,
data cannot be written onto the CD’s.
• If a Blank Cd/Cd-RW(Blank Media) is placed in a
CD-rom, it will not recognize the CD/ Cd-rw.
• What is DVD?
– DVD stands for “Digital Versatile Disk” or “Digital Video
– DVD was first created just to be a bigger CD capable of
holding more info
– A DVD disk can hold between 4.4 and 16gb of data,
depending on the disk
– DVD disks read information off of 2 layers using a blue
• A monitor or display (sometimes called a visual display unit)
is an electronic visual display for computers. The monitor
comprises the display device, circuitry, and an enclosure.
• The display device in modern monitors is typically a thin film
transistor liquid crystal display (TFT-LCD), while older
monitors use a cathode ray tube (CRT).
• The Digital Visual Interface (DVI) is a video interface
standard designed to provide very high visual quality on
digital display devices such as flat panel LCD computer
displays and digital projectors.
• DVI Connection DVI keeps data in digital form from the
computer to the monitor. There's no need to convert data
from digital information to analog information. LCD monitors
work in a digital mode and support the DVI format.
S-Video• Separate Video, more commonly known as S-Video, also
called Y/C, and sometimes incorrectly referred to as Super
Video, is an analog video signal that carries video data as two
separate signals: luma (luminance) and chroma (color).
• This differs from composite video, which carries picture
information as a single lower-quality signal, and component
video, which carries picture information as three separate
higher-quality signals. S-Video carries standard definition
video (typically at 480i or 576i resolution), but does not carry
audio on the same cable.
• In computing, a printer is a peripheral which produces a hard
copy (permanent readable text and/or graphics) of
documents stored in electronic form, usually on physical print
media such as papers.
• Many printers are primarily used as local peripherals, and are
attached by a printer cable or, in most newer printers, a USB
cable to a computer which serves as a document source.
• Impact Printers – Daisy wheel, Drum Printer, Line Printer and
• Non-Impact Printers – Inkjet, Bubble jet and Laser Printers
• The BIOS is special software that interfaces the
major hardware components of your computer with the
Operating system, It is usually stored on a Flash
Memory chip on the motherboard, but sometimes the
chip is another type of ROM.
When you turn on your computer, the BIOS
does several things. This is its usual
1. Check the CMOS Setup for custom settings
2. Load the interrupt handlers and device
3. Initialize registers and power management
4. Perform the power-on self-test (POST)
5. Display system settings
6. Determine which devices are bootable
7. Initiate the bootstrap sequence
Booting the Computer
Whenever the Computer is turned on
computer, the first thing you see is the
BIOS software doing its thing. BIOS
displays text describing things like the
amount of memory installed, the type of
hard disk and so on.
• During this boot sequence, the BIOS
does a remarkable amount of work to
get the computer ready to run. After
checking the CMOS Setup and loading
the interrupt handlers, the BIOS
determines whether the Video card is
• Next, the BIOS checks to see if this
is a cold boot or a reboot. It does
this by checking the value at memory
address 0000:0472. A value of 1234h
indicates a reboot, and the BIOS
skips the rest of POST.
• If it is a cold boot, the BIOS verifies
RAM by performing a read/write test
of each memory address. It checks
the PS/2 ports or USB ports for a
keyboard and a mouse. It looks for
PCI bus and, if it finds one, checks
all the PCI cards. If the BIOS finds
any errors during the POST, it will
notify you by a series of beeps or a
text message displayed on the screen.
An error at this point is almost always
a hardware problem.
CMOS • Also known as a
CMOS RAM, CMOS
is short for
• CMOS is an on-
chip powered by a
stores such as the
and system settings
for your computer.
• The CPU is the brain of the computer. Sometimes referred to
simply as the central processor , but more commonly called
processor, the CPU is where most calculations take place. In
terms of computing power, the CPU is the most important
element of a computer system.
• The CPU itself is an internal component of the computer.
Modern CPUs are small and square and contain multiple
metallic connectors or pins on the underside. The CPU is
inserted directly into a CPU socket, pin side down, on the
• Two typical components of a CPU are the following:
• The arithmetic logic unit (ALU), which performs arithmetic
and logical operations.
• The control unit (CU), which extracts instructions from
memory and decodes and executes them, calling on the ALU
CISC Vs RISC
• This tradeoff in basic instruction set design philosophy is
reflected in the two main labels given to instruction sets. CISC
stands for complex instruction set computer and is the name
given to processors that use a large number of complicated
instructions, to try to do more work with each one.
• RISC stands for reduced instruction set computer and is the
generic name given to processors that use a small number of
simple instructions, to try to do less work with each
instruction but execute them much faster.
• The chipset consists of two major microchips. These are
known as the North bridge and the South Bridge. The North
Bridge Handles data for the AGP Port and the main memory
which includes the FSB (Front side bus).
• Although both chips are required for the PC to work the North
Bridge handles most of the very important tasks such as the
connection between the CPU and main memory. The South
Bridge handles data from the PCI and ISA slots and can also
have integrated components such as Audio codec's etc.
QUAD CORE CPU
• Intel® Quad-Core Technology
• Delivering four complete execution cores
within a single processor, Intel quad-core
technology is the ideal choice when it comes
to your high-performance computing needs.
i3 CPU• The Intel® Core™ i3 processor family with Intel® HD Graphics
delivers a revolutionary new architecture for an unparalleled
computing experience. As the first level in Intel's new
processor family, the Intel Core i3 processor is the perfect
entry point for a fast, responsive PC experience.
• This processor comes equipped with Intel HD Graphics, an
advanced video engine that delivers smooth, high-quality HD
video playback, and advanced 3D capabilities, providing an
ideal graphics solution for everyday computing.
Intel i7 core• Features
• The new LGA 1366 socket is incompatible with earlier
• On-die memory controller: the memory is directly connected
to the processor.
– Three channel memory: each channel can support one or
two DDR3 DIMMs. Motherboards for Core i7 have four
(3+1) or six DIMM slots instead of two or four, and DIMMs
should be installed in sets of three, not two.
– Support for DDR3 only.
– No ECC support.
• The front side bus is replaced by Quick Path interface.
Motherboards must use a chipset that supports QuickPath.
Intel i7 core• The following caches:
– 32 KB L1 instruction and 32 KB L1 data cache per core
– 256 KB L2 cache (combined instruction and data) per core
– 8 MB L3 (combined instruction and data) "inclusive", shared by
• Re-implemented Hyper-threading. Each of the four cores can
process up to two threads simultaneously, so the processor appears
to the OS as eight CPUs.
• Only one QuickPath interface: not intended for multi-processor
• 45nm process technology.
• 731M transistors.
• Sophisticated power management can place an unused core in a
Data Transfer Management By CPU
• PIO Mode
• Interrupt Controller Mode
• DMA Mode
• Programmable Input Output Mode
– In this mode CPU is responsible for Instruction processing
as well as data transfer
– So less performance
– More latency
• In computing, a programmable interrupt controller (PIC) is a
device that is used to combine several sources of interrupt
onto one or more CPU lines, while allowing priority levels to
be assigned to its interrupt outputs.
• When the device has multiple interrupt outputs to assert, it
will assert them in the order of their relative priority.
• Direct memory access (DMA) is a feature of modern
computers and microprocessors that allows certain hardware
subsystems within the computer to access system memory for
reading and/or writing independently of the central
• High performance because data transfer work is done by DMA
controller. CPU is doing only instruction processing work.
–Brownout or sag
• A switched-mode power supply (switching-mode power
supply/SMPS, or simply switcher) is an electronic power
supply unit (PSU) that incorporates a switching regulator in
order to provide the required output voltages (DC).
• Output DC Voltages
– +3.3 v, +5 v, + 12v, -5v, -12v etc …
• A computer or device on a network that manages network
resources. For example, a file server is a computer and
storage device dedicated to storing files.
• A print server is a computer that manages one or more
• A network server is a computer that manages network traffic.
• A database server is a computer system that processes
• Servers are often dedicated, meaning that they perform no
other tasks besides their server tasks. On multiprocessing
operating systems, however, a single computer can execute
several programs at once.
• In the client/server programming model, a server is a program
that awaits and fulfills requests from client programs in the
same or other computers.
• A client does not share any of its resources, but requests a
server's content or service function. Clients therefore initiate
communication sessions with servers which await (listen to)
• A blade server is a stripped down server computer with a
modular design optimized to minimize the use of physical
space and energy.
• Blade servers have many components removed to save space,
minimize power consumption and other considerations, while
still having all the functional components to be considered a
Rack / U Size
• Equipment designed to be placed in a rack is typically
described as rack-mount, rack-mount instrument, a rack
mounted system, a rack mount chassis, sub rack, rack
mountable, or occasionally simply shelf.
• The height of the electronic modules is also standardized as
multiples of 1.75 inches (4.445 cm) or one rack unit or "U".
Operating System - OS• An operating system is a program designed to manage and
run hardwares & other programs on a Computer. A
computer’s operating system is its most important program. It
is considered the backbone of a computer, managing both
software and hardware resources.
• Operating systems are responsible for everything from the
control and allocation of memory to recognizing input from
external devices and transmitting output to computer
displays. They also manage files on computer hard drives and
control peripherals, like printers and scanners.
• System Software / Operating System
• What is an OS?
• CUI OS / GUI OS
• Application Software
• Utility Software
Software / OS
• Software refers to the instructions, or programs, that tell the
hardware what to do. A word-processing program that you
can use to write letters on your computer is a type of
• The operating system (OS) is software that manages your
computer and the devices connected to it. Windows is a well-
known operating system.
• OS does CPU Management
• OS does Memory Management
• OS does Hardware Management
• OS bridges users with computer
• OS gives life to a Computer
• Without OS Computer is a Dead Machine
• Upon OS only All Application Software's will run
Boot Sequence – Win 95
• Power ON – BIOS – POST – BSL – MBR – IO.SYS – SYSINIT –
MSDOS.SYS – CONFIG.SYS – AUTOEXEC.BAT –
Boot Sequence Win XP
• Power on – BIOS – POST – BSL – MBR – NTLDR – BOOT.INI –
NTDETECT.COM – NTOSKRNL.EXE – HAL.DLL – SYSTEM
REGISTRY – WINLOGON.EXE – LSASS.EXE
XP Boot Sequence
• First is the POST, this stands for Power On Self Test, for the
computer. This process tests memory as well as a number of
other subsystems. You can usually monitor this as it runs each
• After that is complete the system will run POST for any device
that has a BIOS (Basic Input-Output System). An AGP has its
own BIOS, as do some network cards and various other
XP Boot Sequence
• Once the POST is complete and the BIOS is sure that
everything is working properly, the BIOS will then attempt to
read the MBR (Master Boot Record).
• This is the first sector of the first hard drive (called the Master
or HD0). When the MBR takes over it means that Windows is
now in control.
XP Boot Sequence
• The MBR looks at the BOOT SECTOR (the first sector of the
active partition). That is where NTLDR is located, NTLDR is the
BOOT LOADER for Windows XP.
• NTLDR will allow memory addressing, initiate the file system,
read the boot.ini and load the boot menu.
• NTLDR has to be in the root of the active partition as do
NTDETECT.COM, BOOT.INI, BOOTSECT.DOS (for multi-OS
booting) and NTBOOTDD.SYS (if you have SCSI adapters)
XP Boot Sequence
• Once XP is selected from the Boot Menu, NTLDR will run
NTDETECT.COM, BOOT.INI and BOOTSECT.DOS to get the
proper OS selected and loaded. The system starts in 16-bit
real mode and then moves into 32-bit protected mode.
XP Boot Sequence
• NTLDR will then load NTOSKRNL.EXE and HAL.DLL. Effectively,
these two files are windows XP. They must be located in
• NTLDR reads the registry, chooses a hardware profile and
authorizes device drivers, in that exact order.
• At this point NTOSKRNL.EXE takes over. It starts
WINLOGON.EXE that in turn starts LSASS.EXE, this is the
program that display the Logon screen so that you can logon.
Error Codes 1xx - System Board errors
2xx - Memory related problem
3xx - Keyboard error
4xx - Monochrome video problem
5xx - Colour video problem
6xx - Floppy disk problem
161 - CMOS battery failure
1701 - HDD problems
1780 - Drive 0 problem
1781 - Drive 1 problem
Run Disk Cleanup
Clear all temp files, cookies, internet temporary files etc.
If needed increase the RAM
Increase virtual memory size
Run Anti-Virus to clear any virus
Check for RAM issues – (clean the RAM pins and re-fix it)
Check CPU fan
Check for any overloading applications
Check for virus issues
FDD Failures• First, make sure the disk is not write protected. The hole on
the right top corner of a 3.5-inch disk (viewed from the front)
should be closed.
• Try another disk.
• Try a new (formatted) disk.
• Try someone else's disk-one that is known to work on another
computer (first make sure there is no critical data on the disk).
• If two or more disks are unreadable, the drive is suspect; try
going to MS-DOS and reading a directory using the DIR
Once a FDD is suspected, change the FDD ribbon cable (34
pins) and verify
Then interchange the power supply pins and check
Check the BOIS settings
Check the suspected drive in a good working computer and
confirm it 100%
Then change the drive itself and verify
Check BIOS settings
Check Master / slave jumper settings
Change the IDE cable and check
Change the power supply Molex connector and check
Clean the IDE port pins and re-fix the cable
Connect to the other IDE connector and check
Check the HDD in good working system and confirm it 100%
before going for replacement
Video Card Problem
Remove the video card clean the pins and slot
Fix it in some other slot and verify
Check the card with a good working system and confirm
Remove the RAM clean it properly and re-fix it
Fix in other RAM slot and check
Check the RAM with a good working system and confirm it
Blue dump memory error – check recently installed
application or hardwares
Check power card issues
Check on-off switch on the Monitor
Disconnect the monitor from VGA card and check for test
signal (RGB flag)
Check with other good working computer and confirm it
Call the Monitor service-Technician and fix the problem
Only single colour, different colour – check for any broken
VGA connector pins or bend pins in the connector
Remove the connector re-fix it properly
Change the VGA cable itself and confirm
Change the VGA card and confirm it
Keyboard and Mouse Problem
Check the keyboard is connected to the correct port
Check the keyboard connector pins are in perfect order
Check the keyboard with other good working system and
Check the mouse is connected to the correct port
Check the mouse connector pins
Check with other good working system and confirm it
Check for all connectors and power supply
connector and cables
Check with other good working system and
Network Connectivity Issues
Check NIC card properly fixed or not
Check network cable
Check RJ45 connector and connection
System date and time always changes after re-setting
Change CMOS battery and check
Check the power supply
Check the CPU fan
Check the CPU with a good working system
Check the Monitor for powered on or not
Check the RAM
Check VGA card
Check VGA card to Monitor connector
Check for proper display settings (correct pixel ratio and
System not booting
Check bios settings for proper boot device order
Check for OS status
Start the system press F8 and choose last known good
Select and try with safe mode
Select and try with command prompt only option
Trouble shooting OS is corrupted not booting
Remove the HDD connect to a good working system and
backup all important data
Try with recovery console mode and repair MBR, Boot etc
Repair the OS with boot CD
Re-install the OS on some other partition and try to
recover valuable data
Finally if all the options are not working delete all
partitions and freshly install the OS after taking proper
NTLDR / HAL.DLL /NTOSKRNL file missing or corrupted
Copy the required file from good working system and
First isolate the system from network, so that spreading the
virus to other systems is avoided
Scan the system with proper anti-virus software
Scan the system with up to date anti-virus
Quarantine the infected file, till you can clear the virus
Inform to the vendor to get a proper patch program
If you can not remove the virus, if data are not important
format the drive and re-install the OS as a final option
Check with multi-meter for correct output voltages
Unplug all power connectors and short green and black wires
in SMPS to verify, SMPS is functioning properly
Fiber Optics• An optical fiber is a thin, flexible, transparent fiber that acts as
a waveguide, or "light pipe", to transmit light between the
two ends of the fiber.
• Optical fibers are widely used in fiber-optic communications,
which permits transmission over longer distances and at
higher bandwidths (data rates) than other forms of
• Fibers are used instead of metal wires because signals travel
along them with less loss and are also immune to
• Optical fiber typically consists of a transparent core
surrounded by a transparent cladding material with a lower
index of refraction. Light is kept in the core by total internal
reflection. This causes the fiber to act as a waveguide.
• Fibers which support many propagation paths or transverse
modes are called multi-mode fibers (MMF), while those which
can only support a single mode are called single-mode fibers
• Multi-mode fibers generally have a larger core diameter, and
are used for short-distance communication links and for
applications where high power must be transmitted. Single-
mode fibers are used for most communication links longer
than 1,050 meters (3,440 ft).
FO• Fiber higher bandwidth.
• Fiber needs less amplification/repeating. Fiber needs repeaters
every 50 km. Copper every 5 km.
• Fiber less affected by electromagnetic interference. But on
downside, easily damaged if bent.
• Fiber thinner and lighter: Makes big difference to telephone
company with thousands of cables.
• For new routes, fiber cheaper to install.
• Massive installed base of copper.
• Fiber more expensive, but clearly the future of all cables of more
than a few metres is fiber.
• Bluetooth is an open wireless technology standard for
exchanging data over short distances (using short wavelength
radio transmissions) from fixed and mobile devices, creating
personal area networks (PANs).
• Infrared (IR) light is electromagnetic radiation with a
wavelength between 0.7 and 300 micrometres, Infrared
imaging is used extensively for military and civilian purposes.
• Military applications include target acquisition, surveillance,
night vision, homing and tracking.
• Non-military uses include thermal efficiency analysis, remote
temperature sensing, short-ranged wireless communication,
spectroscopy, and weather forecasting.
• IEEE 802.11 is a set of standards carrying out wireless local
area network (WLAN) computer communication in the 2.4, 3.6
and 5 GHz frequency bands. They are created and maintained
by the IEEE LAN/MAN Standards Committee (IEEE 802).
• The base current version of the standard is IEEE 802.11-2007.
• The 802.11a standard uses the same data link layer protocol
and frame format as the original standard, it operates in the 5
GHz band with a maximum net data rate of 54 Mbit/s.
• 802.11b has a maximum raw data rate of 11 Mbit/s and uses
the same media access method defined in the original
standard. 802.11b devices suffer interference from other
products operating in the 2.4 GHz band.
• Devices operating in the 2.4 GHz range include: microwave
ovens, Bluetooth devices and cordless telephones.
• In June 2003, a third modulation standard was ratified:
802.11g. This works in the 2.4 GHz band (like 802.11b). It
operates at a maximum physical layer bit rate of 54 Mbit/s.
• 802.11g hardware is fully backwards compatible with 802.11b
hardware. The then-proposed 802.11g standard was rapidly
adopted by consumers starting in January 2003, well before
ratification, due to the desire for higher data rates as well as
to reductions in manufacturing costs.
• Wireless security is the prevention of unauthorized access or
damage to computers using wireless networks.
• Wireless networks are very common, both for organizations
and individuals. Many laptop computers have wireless cards
pre-installed. However, wireless networking has many security
• Hackers have found wireless networks relatively easy to break
into, and even use wireless technology to crack into wired
• As a result, it's very important that enterprises define
effective wireless security policies that guard against
unauthorized access to important resources.
• 802.11 security - WEP stands for Wired Equivalent Privacy.
This encryption standard was the original encryption standard
• WEP is to make wireless networks as secure as wired
networks. Unfortunately, this never happened as flaws were
quickly discovered and exploited.
• There are several open source utilities like aircrack-ng,
weplab, WEPCrack, or airsnort that can be used by crackers to
break in by examining packets and looking for patterns in the
• WEP has some serious issues. First, it does not deal with the
issue of key management at all. Either the keys have to be
manually given to end users, or they have to be distributed in
some other authentication method.
• Since WEP is a shared key system, the AP uses the same key as
all the clients and the clients also share the same key with
each other. A cracker would only have to compromise the key
from a single user, and he would then know the key for all
• In addition to key management, a recently published paper
describes ways in which WEP can actually be broken. This is
due to a weakness in RC4 (40 bit key) as it is implemented in
• WEP is indeed a broken solution, but it should be used as it is
better than nothing. In addition, higher layer encryption (SSL,
TLS, etc) should be used when possible.
• Wi-Fi Protected Access (WPA) is a software/firmware
improvement over WEP. All regular WLAN-equipment that
worked with WEP are able to be simply upgraded and no new
equipment needs to be bought.
• WPA is a trimmed-down version of the 802.11i security
standard that was developed by the IEEE 802.11 to replace
• The TKIP encryption algorithm was developed for WPA to
provide improvements to WEP that could be fielded as
firmware upgrades to existing 802.11 devices. This stands for
Temporal Key Integrity Protocol (TKIP) and the acronym is
pronounced as tee-kip. This is part of the IEEE 802.11i
• TKIP implements per-packet key mixing with a re-keying
system and also provides a message integrity check. These
avoid the problems of WEP.
• The newest and most rigorous security to implement into
WLAN's today is the 802.11i. The primary enhancement over
WPA is the inclusion of the AES algorithm as a mandatory
• Both WPA and WPA2 support EAP authentication methods
using RADIUS servers and preshared key (PSK).
Other Security Measures
• Smart cards, USB tokens, and software tokens, these are all
very strong form of security.
• When combined with some server software, the hardware or
software card or token will use its internal identity code
combined with a user entered PIN to create a powerful
algorithm that will very frequently generate a new encryption
• The server will be time synced to the card or token.
• Generally, the study of measurable biological characteristics is
Biometrics. In computer security, biometrics refers to
authentication techniques that rely on measurable physical
characteristics that can be automatically checked.
• face: the analysis of facial characteristics
• fingerprint: the analysis of an individual unique fingerprints
• hand geometry: the analysis of the shape of the hand and the
length of the fingers
BIO-Metrics• retina: the analysis of the capillary vessels located at the back
of the eye
• iris: the analysis of the colored ring that surrounds the eye
• signature: the analysis of the way a person signs his name.
• vein: the analysis of pattern of veins in the back if the hand
and the wrist
• voice: the analysis of the tone, pitch, cadence and frequency
of a persons voice.
• Hair Pattern