What is Motherboard?
Motherboard is an electronic
printed circuit board. It is also the hub of all computer peripherals. It is
called “mother board” because there are other boards (VGA, Sound, and NIC etc)
that are all attached to this board as well the Microprocessor installed on
this board. All motherboards are properly installed and fixed with screws onto
the cabinet for safety and damage protection.
Southbridge: An integrated
circuit (e.g., Intel
or VIA) on the motherboard
that is responsible for the hard drive
controller, I/O controller and integrated hardware such as sound card,
video card if present on the motherboard, USB, and Ethernet.
Northbridge: An integrated
circuit (e.g., Intel
or VIA) that is responsible
for communications between the CPU interface, AGP, PCI, and the memory.
What is PC Assembling?
PC assembling means to build
a PC system by collecting, connecting and joining the hardware resources to
Motherboard which is already installed and fixed into computer case known as
cabinet. During PC assembling we first setup the motherboard into cabinet then
following resources are connected, attached or inserted with proper care and
settings.
1.
Microprocessor Chip and CPU Cooler/Fan
2.
Extended memory / RAM
3.
Power and Reset LEDs
4.
HDD to IDE or SATA ports
5.
CD-ROM/DVD-ROM drives
6.
SMPS connectors to motherboard and FDD, HDD
and CD/DVD drives
7.
Battery and BIOS config jumper
8.
Keyboard and Mouse connections to PS/2 or USB
ports.
9.
Monitor data cable link
10.
Multimedia components (MIC & Speakers)
What is SMPS?
A switched-mode power supply (switching-mode
power supply/SMPS) is an electronic power supply unit (PSU) that converts the
volt and current characteristics from one form to another and incorporates a
switching regulator in order to be highly efficient.
Unlike a linear power supply, the pass
transistor of a switching mode supply switches very quickly between full-on and
full-off states, which minimizes wasted energy. It regulates either output
voltage or current by switching ideal storage elements, like inductors and
capacitors, into and out of different electrical configurations.
What are the Ports?
A port is the hardware interface that enables
us to connect other peripherals to CPU unit (Cabinet). Port literally means a device that can send
and receive data to and from the computer system. Port is then connected to BUS
which carries the signal between two connected communicating devices. Such as
Mouse and CPU needs COM1/COM2 port to interact.
Extensible Firmware Interface (EFI)
In computers with the Intel
Itanium processor, the interface between a computer's firmware, hardware, and
the operating system. The Extensible Firmware Interface (EFI) defines a new
partition style called GUID partition table (GPT). EFI serves the same purpose
for Itanium-based computers as the BIOS found in x86-based computers. However,
it has expanded capabilities that provide a consistent way to start any
compatible operating system and an easy way to add EFI drivers for new bootable
devices without the need to update the computer's firmware.Types of Ports
Serial Port: An Asynchronous port on the computer
used to connect a serial device to the computer and capable of transmitting one
bit at a time. Serial ports are typically identified by 9-pin (type DB-9) also
called COM (communications) ports example, COM1 and COM2.
Serial ports are used to
connect Mouse, Modem, Printer and Network.
RS232-C (Recommended
Standard) is serial port standard developed by ANSI.
Parallel Port: It is a
communicating hardware interface between the CPU and different peripherals in
bytes/character. The parallel port is found on the back of IBM compatible
computers and is a 25-pin (type DB-25) computer interface commonly used to
connect printers to the computer.
Parallel ports are also used
to connect Scanners, Computer-to-Computer and Terminal. These ports are
identified by LPT1, LPT2 and LPT3. (LPT is the abbreviation for Line Printer).
USB Port: USB is short or
Universal Serial Bus, USB is a standard
that was introduced in 1995
by Intel, Compaq, Microsoft and several
other computer companies. USB is an external
bus standard that supports data transfer
rates of 12 Mbps
and is capable of supporting up to 127 peripheral
devices. USB 2.0, also known as "hi-speed USB", was developed by Compaq, Hewlett Packard, Intel, Lucent, Microsoft, NEC and Philips and was introduced
in 2001.
Hi-speed USB is capable of supporting a transfer rate of up to 480 Mbps and is
backwards compatible, meaning it is capable of supporting USB 1.0 and 1.1
devices and cables.
Ethernet Port: An Ethernet adapter
or Ethernet controller is a term used to describe an Ethernet network card used
to connect a desktop computer to a network (Media / Cable). There is one RJ45
connector that connects a PC to Star LAN another is BNC (Bus Network
Connection) port to connect the PC to BUS LAN.
What is BIOS?
BIOS is the abbreviation for
Basic Input Output System. A computer generally the IBM PC or any IBM
compatible PC has CMOS (Complementary Metal Oxide Semiconductor) as the ROM to
store the “bootstrap loader”. This is also known BIOS setup utility –
responsible for POST (Power-On-Self-Test). In BIOS setup we actually configure
the motherboard resources always at the system startup automatically. Hence a
properly tuned and perfectly installed hardware platform is ready to load the
Operating System, such as DOS, Windows and Linux etc. In this way a good and
properly working PC platform given to user for computing, business and other
electronic activities.
What we can do in BIOS setup?
All motherboards come with
CMOS BIOS (Firmware) already installed. It is also pre-configured at different
hardware known as “factory defaults”. To change and make entries into BIOS
setup we need to press “F2” or “Del” key just after power-on. BIOS setup has
following menus:
Main (Standard CMOS Features):
It gives information about the BIOS version, Date, Time, motherboard, CPU, RAM
etc.
Advanced Configuration: In
this menu “Drive Configuration” is used to workout the settings for HDD
(IDE/ATA & SATA) and CD-ROM/DVD-ROM. The “Peripheral Settings” is used for
Serial/Parallel ports and LAN. The “Floppy Drive” setting is used to
enable/disable FDD. The “USB settings” is used to enable/disable the USB device
and to change other options. The “Video Settings” option is used to modify the
primary display i.e., On-board and/or External
Security: This BISO features
enables us to create, delete and change the password for “supervisor” and
“user”. These password are then used to lock the CMOS setup and System boot.
Boot: This menu option
enables use to select the First/Second/Third boot device order when our system
is connected with CD/DVD-ROM, HDD and Floppy drive. We can also disable “boot”
facility of removable device, USB and Ethernet.
Exit: This menu options helps
us to finally decide about the made changes to CMOS setup i.e., “save and
exit”, “exit without saving”, “load default settings” and “discard changes”.
(BIOS) Device Driver Files
Himem.sys: On DOS platform or
on Windows 95/98 machine, this file is used to configure the Extended memory
(RAM). Since DOS can’t use memory more than 640 KB (base RAM), therefore we
need to create “config.sys” file as follows:
Rem Created for DOS booting
Device=C:\DOS\Himem.sys
/testmem:off
Files=60
Buffer=35
In this way, at the booting
time with DOS (io.sys, msdos.sys, command.com) this file is also loaded into
primary memory. Therefore, it is called Higher Memory Manager System file.
Smartdrv.sys: This is a
system file for DOS platform to be used by OS for advanced read and write
access operations. It enable fast transfer of data between the memory and Disk
drive. This file needs to loaded during booting of DOS with “config.sys” or
“autoexec.bat” system files.
Rem Autoexec file modify
@echo off
Prompt $p$g
Path=C:\; C:\DOS; C:\Tally;
C:\Turboc3
Smartdrv.exe
Ramdrive.sys: This is a
system file used on DOS platform to create a drive letter to access the primary
memory like storage mean. A “Ramdrive” is very fast when loading programs or
writing information. This type of drive only exists till the system is live and
will be lost as the machine is turned off.
It best suitable for “Hard
Disk-less” workstations and LAN, such as DOS based NetWare LAN.
Rem Created for DOS booting –
Rem config.sys file
Device=C:\DOS\Ramdrive.sys
/E:2048
Files=60
Buffer=35
RAM Terminology
1. SDRAM
Short for Synchronous DRAM, SDRAM is a type of DIMM memory that
synchronizes itself with the computer's system clock to provide
the synchronization between the memory and the computer processor
2. SRAM
Short
for Static RAM, SRAM is a type of computer memory that requires a constant
power flow in order to hold information. Although quicker than DRAM, SRAM is much more
expensive and requires more power; therefore, it is commonly only used in cache
and video card memory.
3. DDR
Short for Double Data Rate,
DDR is a type of memory that utilizes both the rising and falling edge of the system
clock that has the potential of doubling the speed of the memory. DDR2 is the
second generation of DDR memory capable of operating at greater speeds of 400
MHz and higher, offers a greater bandwidth potential, and operates at a lower
power consumption generating less heat. Today DDR3 and DDR4 memory is also
available for new generation motherboards and microprocessors, such as Core2
Duo, Dual Core and i2, i3 Intel CPUs.
4. DIMM
Short
for Dual In-line Memory Module, DIMM is a type of circuit board that holds
memory chips. DIMMs have a 64-bit path
because of the Pentium Processor requirements. Because of the new bit path,
DIMMs can be installed one at a time, unlike SIMMs on a Pentium that would
require two to be added.
5. SIMM
Short
for Single In-line Memory Module, SIMM is a circuit board
that holds six to nine memory chips per board, the ninth chip usually an error
checking chip (parity / non parity) and were commonly used with Intel Pentium or
Pentium compatible motherboards.
SIMMs are rarely used today have have been widely replaced by DIMMs.
Primary Memory Terminology
1. Base Memory
It is the main and base
memory that is limited to the size of 640 KB. This small size primary memory
was used by DOS operating system. It is also referred as the conventional
memory.
2. Upper Memory
3. Extended Memory
It is actually the primary
memory that is created by extending the size of base memory (640 KB barrier).
It is not configurable and unavailable to programs other than those that run in
Microsoft Windows and OS/2.
4. HMA
5. Cache Memory
6. Virtual Memory
This is actually the disk
space that has been marked as virtual memory in Ms-Windows to increase the
physically installed primary memory ( RAM ) size in our system. This disk space
is used by Windows at run-time as if it were RAM to load large size
applications and the files / programs. In this way is it is used to make up the
RAM short fall in our system.
How to configure Virtual
Memory
1.
Startà Run : sysdm.cpl
(return)
Or
My Computer Ã
Properties
2.
Advanced à Performance Settings
3.
Advanced à Virtual Memory Change
4.
Select drive other than ‘boot drive’ Ã
Customize
5.
Type minimum and maximum disk area as the page
file size.
e.g., Min. Ã
1024 MB and Max. 2048 MB
Disk Controller
Standards
1. ATA / PATA
Short for AT Attachment, ATA
was first approved in 1994. It is an interface used to connect such devices as
hard disk drives, CD-ROM drives, and other types of drives in IBM compatible
computers. The original ATA interface is now often referred to as PATA
(Parallel AT Attachment) after the introduction of SATA.
2. SATA
Short for, Serial AT
Attachment. SATA 1.0 was first released in August 2001 and is a replacement for
the Parallel ATA interface used in IBM compatible computers. SATA is capable of
delivering 1.5Gbps (150MBps) of performance to each drive within a disk array,
offers backwards compatibility. SATA bus is easy to route, eliminates heat exhaust
problem and take less space in CPU case.
3. ATAPI
Short for AT Attachment
Packet Interface, ATAPI is an extension to ATA that allows support for devices
such as CD-ROM drives, Tape drives and other computer peripherals and not just
hard disk drives.
4. SCSI
It is short for Small
Computer System Interface. Pronounced as "Scuzzy", is the second most
commonly used parallel standard for interface for disk drives capable of
supporting eight devices, or sixteen devices. SCSI-3 was approved in 1996 as ANSI
X3.270-1996. SCSI ports were designed for Apple Macintosh and Unix computers,
but also can be used with PCs.
System Tools
Introduction
System tools in Ms-Windows
are the very much important and more often used software. This type of software
is responsible for keeping our system in good, proper and better condition.
They also help the user and computer operators to solve many basic errors as
well to run different maintenance tasks. Following are the system tools that
are located in Accessories:
1. Disk Cleanup
2. Disk Defragmenter
3. Backup (& Restore)
4. Check Disk / Scandisk
5. System Restore
6. Schedule Task
7. System Information
8. System Security
9. System Configuration
Utility
10. Registry Editor
1. What is Disk Cleanup?
Disk Cleanup helps free up space on your hard
drive. Disk Cleanup searches your drive, and
then shows you temporary files, Internet cache files, and unnecessary program
files that you can safely delete. You can direct Disk Cleanup to delete some or
all of those files. There is also a choice to find installed applications and
to uninstall if not necessary or unwanted.
2. What is Check Disk (chkdsk.exe)?
It is used to find and repair the errors on
the storage media Hard Disk. It very much important in Windows 2000/XP in the
sense that it can be executed to repair the file system and booting problem
from the command prompt. Check disk command creates and displays a status
report for a disk based on the file system.
Usage:
C:\>chkdsk
(without parameter to displays the status of
the disk in the current drive).
C:\>chkdsk /f /r /x
/f: Fixes errors on the disk.
/r: Locates bad sectors and recovers readable
information.
/x:
Use with NTFS only to force the volume to dismount
first, if necessary.
3. What is Backup?
The Backup utility helps you create a copy of
the information on your hard disk. In the event of original data on
your hard disk is accidentally erased or overwritten, or becomes inaccessible
due to hard disk malfunction, you can use the copy to restore lost or damaged
data. It is a graphical interface having wizards to Backup, Restore and
Automated System Recovery.
Types of backup
The Backup utility supports five methods of
backing up data on your computer or network.
1. Copy backup
A copy backup, copies all selected files but
does not mark each file as having been backed up.
2. Daily backup
A daily backup copies all selected files that
have been modified the day the daily backup is performed. The backed-up files
are not marked as having been backed up.
3. Differential backup
A differential backup copies files created or
changed since the last normal or incremental backup. It does not mark files as
having been backed up.
4. Incremental backup
An incremental backup backs up only those
files created or changed since the last normal or incremental backup. It marks
files as having been backed up.
5. Normal backup
A normal backup, copies all selected files
and marks each file as having been backed up. You usually perform a normal
backup the first time you create a backup set.
System State Backup
In Backup, a collection of
system-specific data that can be backed up and restored. The System State data
includes the registry, the COM Class Registration database, and the system boot
files. For servers, the System State data also includes the Certificate
Services database (if the server is operating as a certificate server). If the
server is a domain controller, the System State data also includes the Active
Directory directory services database and the SYSVOL directory.
What is (Backup) Restore?
Restore Wizard in backup utility is used to
recover the lost files and data from previously created backup source. To
restore the original files/data you must select the appropriate the source from
the available backup catalogs and highlight the one or more items.
Backup Tasks
1.
Create the “Normal” backup for complete folder
called “Turboc3” on your HDD. Place the backup source on another Drive.
2.
Create the “Normal” backup for following three
folders in C: to D: as “all-software.bkf”
a.
PC-ABC
b.
Turboc3
c.
FoxPro
3.
Restore “Turboc3” original folder from the
backup first backup source after deleting “Turboc3” in C:/D: drive.
4.
Restore only the “FoxPro” original folder from
the second backup source after deleting “FoxPro” in C:/D: drive.
5.
Create a backup schedule to automatically run
daily at 3:30 PM for any one folder in “Windows\system32\”
Disk Defragmenter overview
Disk Defragmenter analyzes
local volumes and consolidates fragmented files and folders so that each
occupies a single, contiguous space on the volume.
As a result, your system can
access files and folders and save new ones more efficiently. Disk Defragmenter
also consolidates a volume's free space, making it less likely that new files
will be fragmented. The amount of time that defragmentation takes depends on
several factors, including volumes size, the number and size of files and the
available local system resources.
Disk Defragmenter can
defragment volumes having file system, FAT32 and NTFS.
System Restore overview
System Restore is a component
of Windows XP Professional that you can use to restore your computer to a
previous state, if a problem occurs, without losing your personal data files.
System Restore monitors
changes to the system and some application files, and it automatically creates
easily identified restore points. These restore points allow you to revert the
system to a previous time.
System Restore points are
created daily and at the time of installation of applications or drivers and
hardware components. You can also create and name your own restore points at
any time.
Registry Editor
A database repository for
information about a computer's configuration. The registry contains information
that Windows continually references during operation, such as:
- Profiles
for each user.
- The
programs installed on the computer and the types of documents each can
create.
- Property
settings for folders and program icons.
- What
hardware exists on the system.
- Which
ports are being used.
The registry
is organized hierarchically as a tree and is made up of keys and their subkeys,
hives, and value entries.
Tutorial Topics
1.
Mainframe:
Mainframes usually use
proprietory circuits and or generally more powerful than a typical mini
computer. It is a large, fast, multiuser computer system, often utilizing
multiple processors, designed to manage large amounts of data and complex
computing tasks. Mainframes are normally installed in large corporations,
universities, or military installations.Some of distinguishing features are:
*). All processing at one central location
*). All processing at one central location
*). 32/64-bit addressing
*). Large amount of RAM and storage capacities
*). Large number of users (100’s even Thousands)
*). Designed for client/server business computing
2.
Workstation
It is basically a Personal
Computer system with little but complete hardware required to enable it as a
platform in a network. It is used to access to network, network resources and
download applications from the server system. It can boot itself, may have
local RAM, Microprocessor but is dependent on server for file storage,
applications and printing etc. Example: a PC in Cyber Café and a computer in
Bank used to execute normal business.
Printer &
Print Management Tasks
What is Printer?
Printer is an output device
that we can connect to CPU to produce the “hard copy” of processed data or
information known as result and reports. It is a peripheral device which
capable of communication to-and-fro the computer via parallel/serial and USB
ports. Printers are categorized as follows:
Character
Printer Line Printer Page Printers
All the above printers are
classified into two types: 1). the impact printers and 2) the non-impact
printers.
What is Dot Matrix Printer
(DMP)?
The term DOT matrix refers to
the process of placing dots
to form an image; the quality of the image being determined by the DPI (Dots
Per Inch). This printer
use print heads to shoot ink or strike an ink ribbon to place hundreds to
thousands of little dots to form text and/or images. DMP printers have low
quality print-outs compared to ink jet
printers.
What is an Ink Jet printer?
It is a popular type of
character printer
for home computer users and in business. It prints by spraying streams of
quick-drying ink on paper. The ink is stored in disposable ink cartridges,
often a separate cartridge is used for each of the major colors. These colors
are usually Black, Red/Magenta, Green/Cyan, and Yellow (CYMK).
Although inkjet printers
inexpensive but the ink cartridges used in the printing increase the overall
cost of the printer.
What is a Laser Printer?
First developed by Xerox and released in 1971, a laser printer is a
page-printer that utilizes laser
technology to print images on the paper. Its printing speed is measured in
terms of PPM.
Laser printers are often used
in corporate, school, and other environments that require print jobs to be
completed quickly and in large quantities. It has following step before
printing.
Cleaning: Removes prior image
information and toner from the drum.
Conditioning: Applies a
uniform negative charge to the drum.
Writing: Light source such as
lasers, write to areas on the drum discharging the negative potential where it
hits.
Developing: The toner is
ionized with a negative charge and is attracted to the areas previously written
(discharged) on the drum.
Transfer: The toner of the
drum is transferred to the paper by roller.
Fusing: With heat and
pressure toner melts and then is pressed to the paper
What
is Spooling?
The term SPOOL is short
Simultaneous Peripheral Operations On-Line. Spooling is an important function
of any operating system related to print-outs. All print jobs are managed by
“print manager” (Spooler); for the installed local and/or network printers.
Spooler is a service which always runs in the background to accept the print
requests, to direct the print jobs to default printer, to create a print queue
and to cancel the prints jobs etc. To view the print spooler we need to open
“printer and faxes” folder.
Installing a printer
To install a printer on the
local computer system, following steps are required:
1.
Connect the printer to CPU at
Serial/Parallel/USB ports as the data cable is available.
2.
Connect the printer to electrical switch with
power cord.
3.
Startà Settingsà Printer
& Faxes
4.
Printer & Faxes folderà Add
Printer
5.
Add Printer Wizard then display series of
dialog boxes:
a. Welcome
Step
b. Choose
between local or network printer (Select “local”)
c. Select
the appropriate Port (LPT1, COM1, USB)
d. Select
the Manufacturer and Printer model (Example: Epson, Lx-800)
e. Printer
driver file will be copied to system folders. (You may need to provide device
driver source).
f.
Give a name to printer, and select “Yes/NO” to
default printer.
g. Let
the printer sharing “enable” or “not-enable”
h. If
enabled, provide a share name
i.
Specify the location and some comment
j.
Say “yes/no” to test page print
k. Finish
What
is Compression?
File Compression is a
software technique to enable us to store the large size files, documents and
even the folders in less space on the storage media. Another advantage about
the “compression” is saving on time taken to transferring and less bandwidth on
the networks. Sometimes, with compression we can create security as encrypted
and password protected. Some popular compression tools are:
1.
pkzip/pkunzip
2.
WinZip
3.
WinRar
4.
JAR
CabPack is a compression
program with which you can create cabinet (.CAB) files.
When Windows 95 came out,
Microsoft introduced a new compression scheme for their distribution media: the
cabinet files. I was curious: What is the compression rate of the CAB format,
in comparison to other archivers? So I extracted the files from a cabinet file
and re-compressed them using various popular compressors, including ZIP, ARJ
and RAR, and even with maximum compression enabled, I was unable to achieve the
same tight compression the original .CAB file had.
So I began searching for a
utility that allowed me to create my own cabinet files. For over a year I was
unable to find anything. Then, in 1997, Microsoft put up a CAB-SDK (cabinet
software development kit) on their website. The CAB tools contained therein,
however, were all command-line driven, and if you wanted to create .CAB files
that spanned multiple disks, you had to create a so-called "directive
file" which contained all necessary information and had to be passed over
to the CAB compressor.
This was why I decided to
write CabPack. It started out as a console application but has now developed
into a true 32bit GUI program which makes it very easy for the user to create
cabinet files. With just a few mouse clicks you specify which files to
compress, which compression method to use, where the output files should go and
whether or not the cabinet files should span multiple disks. CabPack is able to
store subdirectories, and depending on the platform you wish to extract the
cabinets on, it can create .CAB files that contain long filenames or store
these long filenames in the 8.3 format.
What is PkZip: It is a file
compression tools that we can use from Command Prompt (Ms-DOS). It help us to
create “zip” files for original files and folders not only to save disk space
but also to backup the data. “PkZip” is a command line oriented tools (CUI)
therefore it can be little difficult compared to Windows Explorer “New-->
Compressed Folder” command (GUI).
Step1 (Prepare a folder
“Save1” as follows
Step2:
C:\...\Save1>pkzip -a -r AllOne.zip
.\html\*.*
C:\...\Save1>pkzip -a -r –s AllOne.zip
.\html\*.*
(for password lock)
Creating ZIP: AllOne.ZIP
Adding: ABC/
Storing ( 2%), done.
Adding: ABC/
Storing ( 2%), done.
What is PKUnzip?
This is opposite to “PkZip”.
It is used to extract files from the
“.zip” compressed file.
Step1:
C:\...\Save1>pkunzip -d AllOne.zip
.\html\
Or
C:\...\Save1>pkunzip -d –s AllOne.zip
.\html\
(for password lock file
Creating
Compressed Folder in Windows XP
We can create compressed
format folder in Windows Explorer very much easily and quickly. It more user
friendly than other tools, such as Pkzip/Pkunizp, WinRar, WinZip etc.
Steps:
1.
Being in any folder window or on Desktop
2.
File (Right Click in Window area) Ã
NewÃ
Compressed (Zipped) Folder
3.
Give a name
4.
Now move (copy/cutà paste)
the source files/folders that you want to zip/compress.
5.
(Optional) FileÃ
Add Password (to lock the zip source or to protect unauthorized access).
What
is WinRAR?
WinRAR is a 32-bit Windows version of the RAR
archiver - a powerful tool which allows you to create, manage and control
archive files. There are two versions of RAR for Windows:
1. WinRAR
(Graphical user interface)
2. Rar.exe (Command
line console (text mode)
WinRAR features include:
Ø Complete
support of RAR and ZIP archives,
Ø Highly
sophisticated, original compression and Special algorithms optimized for text,
audio and graphics,
Ø Shell
interface including drag-and-drop facility and wizard,
Ø Command
line interface, Non RAR archives (CAB, ARJ, LZH, TAR, GZ, ACE, UUE, BZ2, JAR,
ISO) management,
Ø Multivolume
archives,
Ø Creation
of self-extracting archives,
Ø Recovering
physically damaged archives,
Ø Support
for Unicode in file names,
Ø Other
service functions, such as encryption, archive comments, error logging, etc.
What is WinZip?
WinZip makes it easy for Windows users to
work with archives. WinZip features an intuitive point-and-click drag-and-drop
interface for viewing, running, extracting, adding, and deleting files in
archives with a standard Windows interface, and also provides a Wizard
interface that further simplifies the process of working with Zip files. These
are:
- WinZip
Classic: It is preferred if you have a general understanding of Windows
and of Zip files. You will be quite comfortable with its Explorer-like
interface once the basics of Zip files are understood.
- WinZip
Wizard: It guides you through some of the most common operations involving
Zip files. If you are new to Windows or unfamiliar with Zip files, start
with the Wizard and switch later to the more powerful Classic interface.
Other features are:
Display Thumbnails in
WinZip's Explorer Style View, View Compressed Images Directly From Your Zip
File, FTP Upload Existing Zip Files, Zip and Burn Directly to CD and DVD Command
Line Support (Separate Download), Improved Compression (WAV), Extract from .BZ2
and .RAR files, Large Zip File Support, 128- and 256-Bit AES Encryption, E-mail
Support (including one-click Zip & E-mail), Split Zip File Capability, Create
Self-Extracting Archives
What is a Self-Extracting Zip File?
A self-extracting Zip file is an executable
program file (.EXE file) that includes a Zip file and software to extract or
"unzip" the contents of the Zip file. Users can run (execute) a
self-extracting Zip file just as they run any other program.
A self-extracting Zip file can be created by
WinZip Self-Extractor Personal Edition or WinRAR Gold Edition.
Installing Windows XP (From CD)
1
|
Make Sure that CD/DVD-ROM
Drive is installed and has been detected in BIOS setup.
|
2
|
Make “First Boot Device” to “CD-ROM”
|
3
|
Save BIOS setup & Exit
|
4
|
Insert “XP Bootable CD-ROM”
in CD-Drive
|
5
|
Let the system Boot from CD
|
6
|
Windows Setup will be
launched and the System Files will be copied to primary memory
|
7
|
Setup is Starting Windows
|
8
|
Enter to Install ( R to Repair )
|
9
|
Press “F8” to accept
license
|
10
|
Disk partitioning
(Press ‘C’ to create, ‘D’
to Delete etc)
|
11
|
Enter on Any of the newly
created disk partition to install OS
|
12
|
Select disk partition
format method (FAT/NTFS)
|
13
|
Formatting will be done
|
14
|
Setup copies files to
windows installation folders on the HDD
|
15
|
System will be restarted
|
16
|
GUI five step windows setup
mode
1)
Collecting information
2)
Dynamic update
3)
Preparing installation
4)
Installing Windows
5)
Finalizing Installation
|
17
|
User Name, Organization
|
18
|
Windows System Name,
Password for Administrator
|
19
|
Date, Time and Time Zone
|
20
|
Network Setting (if NIC is
there): Typical or Custom
|
21
|
Workgroup
|
22
|
Boot.ini
It is a simple ASCII text
file present in root directory of C: drive. It is used on Windows platform to
provide a booting choice between (dual booting) two or more installed operating
systems, such as DOS, Windows 9x, Windows 2000 and Windows XP. It displays
itself each time PC is switched on, then it loads the operating system either
“default” or as selected by the user.
Modifying the Boot.ini file
incorrectly may prevent your computer from restarting. Be sure to edit after
creating a backup copy.
Step1: Startà Run:
attrib c:\boot.ini –h –s
Step2: Startà Run:
Notepad c:\boot.ini
Step3:
Change the time,
Change the OS label in
between double quotes (“”) only
Change the default OS
Step4: Save & Exit
Step5: Startà Run:
attrib c:\boot.ini +h +s
Step6: Reboot System to
confirm the changes.
Installing Windows XP (Local
/ Network Source)
1
|
Make sure that the Windows
XP dump is available by Browsing/Exploring
|
3
|
Run “Setup.exe”
|
4
|
Installation Type: Upgrade
or New Installation
(Select upgrade if the
existing OS is old or little damage)
|
5
|
License (Accept)
|
6
|
Provide the Product Key
|
7
|
Windows Setup Options
(Windows Directory Name and Source Path etc)
|
Windows Setup will be
launched and the System Files will be copied to primary memory
|
|
System will be restarted
|
|
8
|
Enter to Install ( R to Repair )
|
Old Windows folders will be
shown if exists & ask to Repair(R) or Don’t Repair(Esc)
To install newer Window XP
Choose Esc
|
|
10
|
Disk partitioning
(Press ‘C’ to create, ‘D’
to Delete etc)
|
11
|
Enter on Any of the newly
created disk partition to install OS
|
12
|
Select disk partition
format method (FAT/NTFS)
|
13
|
Formatting will be done
|
14
|
Setup copies files to
windows installation folders on the HDD
|
15
|
System will be restarted
|
16
|
GUI five step windows setup
mode
6)
Collecting information
7)
Dynamic update
8)
Preparing installation
9)
Installing Windows
10)
Finalizing Installation
|
Regional Language Options
|
|
17
|
User Name, Organization
|
18
|
Windows System Name,
Password for Administrator
|
19
|
Date, Time and Time Zone
(New Delhi/Kolkatta)
|
20
|
Network Setting (if NIC is
there): Typical or Custom
|
21
|
Workgroup (Depends on the
previous step/NIC)
|
22
|
Preparing Windows Operating environment by
copying, setup and registration of components
|
System Will Reboot
|
|
Display Settings : OK &
OK
|
|
Welcome To Newly Installed
XP Ã
Next
|
|
Help Protect Ã
Not Right now à Next
|
|
Create users:
|
|
Finish
|
What is an Anti Virus Software or
Package?
Introduction
VIRUS is a program which has
been intentionally written to create havoc and cause damages to our computer
system and network resources. Therefore, an Anti-VIRUS software has also been
developed to detect, scan, block and to remove viruses safely from infected
resources in different ways i.e. manually, automatically and in real-time. Most
Anti-VIRUS programs/software is available to users as Package.
An anti-virus package
provides many tools, such as: Virus Scanner, Virus Guard, Anti-Malware,
Anti-Spam, Anti-Phishing, Virus Definition Database, Updater, Firewall,
Anti-Root Kits, and Anti-Spy Ware etc. It is responsible for not only detecting
and scanning but also performs following actions: Repairing infected items,
Deleting/ Renaming if repair fail, Block/Deny access to sensitive resources
e.g. Registry, Quarantine and Do nothing etc. Popular Anti-virus Packages are:
Symantec Corporate Edition, MacAfee Security etc.
What is Quarantine: It means
to move the affected files to a special directory so that the VIRUS file never
get executed and launched.
What is Luke File Walker:
During an on-demand scan, the status window Luke File walker appears, which
provides you with exact information on the status of the scan.
----------------X----------------------------------------------------------------------------------------X-----------
Boot Sector Virus: This type
of Virus is responsible for removing/damaging the “boot record” present in
first sector or MBR (Master Boot Record) so that the booting process can’t take
place.
Command.com Virus: This type
of Virus is responsible affecting the “shell program” on DOS platform so that
actual tasks are hacked.
.EXE Virus: This type of
Virus is responsible for executing itself by attaching to any program file on
our system. Thereby no file is saved or retrieved to-and-fro the storage media.
Partition table Virus: This
type of Virus is responsible for removing/damaging the partition table on the
hard disk drive/pen drives.
1.
Die Hard
2.
I Love You
3.
W.32 (A,B,C,D)
4.
StauxNet
Types/Categories
of Virus
----------------------------------
Trojans:
Trojans are
pretty common nowadays that pretend to have a particular function, but that
show their real image after execution and carry out a different function that,
in most cases, is destructive.
Trojan
horses cannot multiply themselves and have an interesting name. After execution
they become active and can, for example, format the hard disk.
Worms
A worm is a
program that multiplies itself but that does not infect the host. Worms can
consequently not form part of other program sequences. Worms are often the only
possibility to infiltrate any kind of damaging programs on systems with
restrictive security measures.
Other Types
Adware: An Adware is software
that presents banner ads or in pop-up windows through a bar that appears on a
computer screen. These advertisements usually cannot be removed and are
consequently always visible. The connection data allow many conclusions on the
usage behavior and are problematic in terms of data security.
Backdoors: A backdoor can
gain access to a computer by going around the computer access security
mechanisms.
A program that is being
executed in the background generally enables the attacker almost unlimited
rights. User's personal data can be spied with the backdoor's help, but are
mainly used to install further computer viruses or worms on the relevant
system. The connection data allow many conclusions on the usage behavior and
are problematic in terms of data security.
Boot
viruses: The boot or master boot sector of hard disks is mainly infected by
boot sector viruses. They overwrite important information necessary for the
system execution. One of the awkward consequences: the computer system cannot
be loaded any more…
Bot-Net: A bot net is defined
as a remote network of PCs (on the Internet), which is composed of bots that
communicate with each other. A Bot-Net can comprise a collection of cracked
machines running programs (usually referred to as worms, Trojans) under a
common command and control infrastructure. Bot-Nets serve various purposes,
including Denial-of-service attacks etc., partly without the affected PC user's
knowledge. The main potential of Bot-Nets is that the networks can achieve
dimensions on thousands of computers and its bandwidth sum bursts most
conventional Internet accesses.
Honeypot: A honeypot is a
service (program or server) installed in a network. It has the function to
monitor a network and to protocol attacks. This service is unknown to the
legitimate user - because of this reason he is never addressed. If an attacker
examines a network for the weak points and uses the services which are offered
by a Honeypot, it is logged and an alert is triggered.
Macro viruses: Macro viruses
are small programs that are written in the macro language of an application
(e.g. WordBasic under WinWord 6.0) and that can normally only spread within
documents of this application. Because of this, they are also called document
viruses. In order to be active, they need that the corresponding applications
are activated and that one of the infected macros has been executed. Unlike
"normal" viruses, macro viruses do consequently not attack executable
files but they do attack the documents of the corresponding host-application.
Pharming: Pharming is a manipulation
of the host file of web browsers to divert enquiries to spoofed websites. This
is a further development of classic phishing. Pharming fraudsters operate their
own large server farms on which fake websites are stored. Pharming has
established itself as an umbrella term for various types of DNS attacks. In the
case of a manipulation of the host file, a specific manipulation of a system is
carried out with the aid of a Trojan or virus. The result is that the system
can now only access fake websites, even if the correct web address is entered.
Phishing: Phishing means
angling for personal details of the Internet user. Phishers generally send
their victims apparently official letters such as emails that are intended to
induce them to reveal confidential information to the culprits in good faith,
in particular user names and passwords or PINs and TANs of online banking
accounts. With the stolen access details, the phishers can assume the
identities of the victims and carry out transactions in their name. What is
clear is that banks and insurance companies never ask for credit card numbers,
PINs, TANs or other access details by email, SMS or telephone.
Rootkit: A rootkit is a
collection of software tools that are installed after a computer system has
been infiltrated to conceal logins of the infiltrator, hide processes and
record data - generally speaking: to make themselves invisible. They attempt to
update already installed spy programs and reinstall deleted spyware.
Script viruses and worms:
Such viruses are extremely easy to program and they can spread - if the
required technology is on hand - within a few hours via email round the globe.
Script viruses and worms use
one of the script languages, such as Javascript, VBScript etc., to insert
themselves in other, new scripts or to spread themselves by calling operating
system functions. This frequently happens via email or through the exchange of
files (documents).
A worm is a program that
multiplies itself but that does not infect the host. Worms can consequently not
form part of other program sequences. Worms are often the only possibility to
infiltrate any kind of damaging programs on systems with restrictive security
measures.
Spyware: Spyware are so
called spy programs that intercept or take partial control of a computer's
operation without the user's informed consent. Spyware is designed to exploit
infected computers for commercial gain.
Trojan
horses (short Trojans): Trojans are pretty common nowadays. We are talking
about programs that pretend to have a particular function, but that show their
real image after execution and carry out a different function that, in most
cases, is destructive. Trojan horses cannot multiply themselves, which
differentiates them from viruses and worms. Most of them have an interesting
name (SEX.EXE or STARTME.EXE) with the intention to induce the user to start
the Trojan. Immediately after execution they become active and can, for
example, format the hard disk. A dropper is a special form of Trojan that
'drops' viruses, i.e. embeds viruses on the computer system.
Zombie: A Zombie-PC is a
computer that is infected with malware programs and that enables hackers to
abuse computers via remote control for criminal purposes. On command, the
affected PC starts denial-of-service (DoS) attacks, for example, or sends spam
and phishing emails.
Installing Device Drivers
1. Display Adapter (Steps)
a. Start-->Run : DevMgmt.Msc
b. Other devices (+)
c. Right Click "Video Controller"Ã Update
Driver
d. Hardware Wizard-->No Not this time
e. What do you want wizrad to do
() Install from
a list (Advanced)
f. Choose Search & Installtion Option
() Don't Search
g. Hardware Types-->Display Adapter
h. Select the device driver you want
Select Any one:
() Manufacture
then product model
OR
() Have Disk
(best)
i. Install from --> Browse the location
j. Find the correct directory for "Look in"
then pick the
".inf" file-->Open
k. Path is now completed in "Copy manufacturers
files from"--> OK
l. Select the best device driver from "Show Comapatible H/W"-->Next
m. Observe the copying of device files
n. Completing H/W install-->Finish
What is a File System?
File System is a technique
and the mechanism responsible for file handling on the storage devices. In any
operating system, the overall structure in which files are named, stored, and
organized is build when then storage media is formatted. NTFS, FAT, and FAT32
are types of file systems on Windows and HPFS is on OS/4. It has following
components:
q Boot
Record
q FAT: The file allocation table (FAT) is a data
structure that Windows creates when you format a volume by using the FAT or
FAT32 file systems. Windows stores information about each file in the FAT so
that it can retrieve the file later.
q Track
q Sectors
q Cluster
q Cylinders
q Block
Types of File Systems
1. NTFS file system
An advanced file system that
provides performance, security, reliability, and advanced features that are not
found in any version of FAT. For example, NTFS guarantees volume consistency by
using standard transaction logging and recovery techniques. If a system fails,
NTFS uses its log file and checkpoint information to restore the consistency of
the file system. In Windows 2000 and Windows XP, NTFS also provides
advanced features such as file and folder permissions, encryption, disk quotas,
and compression.
2. FAT32
A derivative of the file
allocation table (FAT) file system. FAT32 supports smaller cluster sizes and
larger volumes than FAT, which results in more efficient space allocation on
FAT32 volumes.
How to convert the File System?
To convert the files system (upgrade) from FAT32 to
NTFS “convert” command is used on the command prompt with “Administrator”
account.
1 Computer Networks
Definition: A network is
group of computers that can communicate with each other, share resources (such
as HDD, printer) and access remote hosts or other networks.The basic hardware
components of a network are
1. one or
more servers
2. Workstations/Clients/Nodes
3. peripheral
devices(Modem,Printer etc)
4. network
boards (NIC)
5. communication
media(Wire/Wireless)
What is Local Area Network?
LAN is group of homogeneous
computers (all IBM compatible or ‘all
Mac systems) connected to each other or to a server computer either
directly or indirectly.
A LAN is basically used in a
small office or corporate situated within a building. A LAN can be spread over
1-10 kilometer distance.
The purpose of LAN is to
group two or more computers to enable communication with each other, share
resources (such as HDD, printer, Internet connection etc) and access remote
hosts.
The basic hardware components
of a LAN are:
1. One or
more servers
2. Workstations/Clients/Nodes
3. Peripheral
devices (Modem, Printer etc)
4. Network
boards (NIC)
5. Media
(Wire/Wireless)
6. Communication
protocols
7. Switch or HUB
3. Computer Network Architectures
1.Peer-To-Peer (P2P)
In this architecture,
computers are connected to each other in the network directly, via the media
and switch/hub. There is no server computer at all. Instead each computer in
the network itself works as client and server both.
2. Client/Server
In this network all the
participating computers are connected to a server computer. All the
communication takes place via the server only. The server computer is use to
provide the services (File hosting, Printing, Internet Connection, Database and
E-mail etc.)to the clients. Clients send requests to the server to access the
network and network resources, whereas server provides services to the clients
using there permission and rights chart.
Client/Server network concept
can be implemented in LAN also with BUS and Star topologies. Applications of
this network architecture are: ISPs, E-mail system, IRC system, WWW system and
USEnet etc.
What is LAN (Network) Topology
It is the map of the network.
Physical topology describes where the cables are run and where the
workstations, nodes, routers, and gateways are located. Following are the LAN
topologies.
1. BUS
Topology
In this topology the clients
are connected to server serially one after another, using single coaxial cable.
Hence a message in the network is picked up by all clients at once. Data
collision occurs at each node. It is also called Ethernet.
A protocol called CSMA/CD (Carrier
Sense Multiple Access/ Collision Detection) is being used to control the data
traffic in the network also to solve the data collision problem.
coaxial-cable |
2. STAR
topology
A network topology in the
form of a star. At the center of the star is a wiring hub and the nodes and
workstations are arranged around the central point representing the point of
the star. There is no data collision between the clients and other devices.
This network is more popular and simple to build, run and manage. UTP
(Un-Shielded Twisted Pair) cable is used to provide the path to communicate
with server and other clients. RJ45 plastic connectors are used at both ends of
the cable to connect NIC-Switch, NIC-HUB and NIC-NIC.
3. Ring
Topology
In this topology coaxial
cable is used in ring shape with no end points. A LAN with a ring structre uses
“token” to regulate traffic on the network and avoid collision.
The controlling NIC generates
a token that controls the right to transmit, When a node has information to
transmit, it captures the token, set its status to busy, and ads the message
and the destination address. The token continuously passed from one node to
another around the network.
Wide Area Network
When a network crosses the geographical
boundaries of cities/states, it is called a WAN.It is a public network such as
PSTN (Public Switched Telephone Network).
A WAN is a digital communication system which
interconnects different sites, computer installation and user terminals.In a
WAN, the transmission medium used are normally public systems such as telephone
lines (physical), microwave and satellite links (non-physical).
WAN is also called long haul
network. Example networks are: PSTN (Public Switched Telephone Network, PSDN
(Public Switched Data Network), ISDN (Integrated Services Digital network), VPN
(Virtua Private Network) and CRIS (Central
Railway Information System) etc.
Difference
between LAN and WAN
LAN
|
WAN
|
It is restricted to a
limited geographical area of few
kilometers
|
It span across the
geographical boundaries of cities and states.
|
It is a private network
|
It is a public network
|
cost of data transmission
is negligible
|
We need to pay for data
transfer to service provider in different tariff rates.
|
Data transmission is much
higher and in large volume
|
It is a slow network and
difficult to transfer data in large volumes
|
communication and link
breakdown rarely occurred
|
communication failures and
link breakdown occur more often
|
LAN is a digital only
transmission technology (but WiFi)
|
WAN provide both ways of
transmission: analog and digital
|
NIC is used as MAC
|
Router and HUB are used for
networking
|
What is Media?
Definition: The path which carries the signal
(messages and data) from one communicating device to another is known as media.
Generally the media is cable which is physical, but wireless technology such as
Radio waves, Microwaves and Infra Red rays are also called media.
Types of Media
1. Coaxial Cable
It is a high capacity cable, which can
transmit data at high rate. The cable, contain a solid inner copper Conductor
surrounded by plastic insulation and outer braided copper or foil shield.
Other features:
1. Totally
free from external interference
2. Permits high volumes of transmission rates
3. Suitable for long distance
4. Permits data transmission up to 10-100
Mbps.
Types of Coaxial cable
1. Thick
Coaxial (10Base5)
for WAN, TV network
2. Thin Coaxial (10Base2) for LAN
2.UTP Cable
UTP or Un-Shielded Twisted Paired cable is
the most commonly used computer network media. It contains 8 copper wires which
are paired into four physical paths, used to transmit the digital signal via
switches and hubs. This cable is part of the “ARCnet” (Attched Resources
Computer Network) as well standardized according to Ethernet 10BASE2.Since it
lack shielding therefore prone to external interference hence widely used in
LAN. RJ45 plastic connectors are used at both ends. It is used in STAR network
topology also for ISDN.
Types of Coaxial cable
1 CAT 5 type UTP cable
This is the most commonly
used UTP cable category in computer networks. CAT 5 comes in either solid core
or standard cabling. This technology is designed to support digital voice and
data communication at speed up to 100 Mbps. In CAT 5 UTP cable there are 4
twisted pairs copper wires protected with insulating sheath.
2 CAT 6 UTP cable
The CAT 6 UTP cabling is used
in Ethernet and Gigabit Ethernet networks including LAN and WAN both. A CAT 6
type of UTP cable consists of 4 twisted pairs of copper wires with protective
sheath. This category of UTP wiring is designed to provide quality of service,
fast data transfer and speed up to 1 Gbps. ISPs and other public networks provide
communication services to their clients for which money is paid.
3 CAT 3 UTP cable
This type of UTP
cable is consists of 2 insulated
wires gently twisted together. Four such
pairs are typically grouped together is a plastic sheath for protection. Since
it has less twists / centimeter, is therefore prone to ‘Cross Talk’ and signal
becomes weak with long distance.
UTP Signaling
Terms
1. Impedance: 100 Ohms,
2. Frequency rating: 100MHz,
3. Capacitance 13.5 to 17 Pico
Farads/foot,
4. Attenuation (low is good) 23 to
67dB/1000 feet,
5. Crosstalk (low is good) 32 to 51 dB at
1000 feet.
How UTP cable
wiring is done?
1. Straight through UTP cable
In this UTP cable wiring
method following pairing and positioning is used at two ends. The straight through UTP
cable is used to connect a PC to switch or PC to HUB as well to connect the a
Switch to Switch.
A straight-thru UTP Cable is
used as a patch cord in Ethernet connections.
2. Cross Over UTP cable
A cross over UTP cable is use
to connect the PC-to-PC or Switch to HUB or HUB-to-HUB.It’s wiring with RJ45
connector looks like as follows:
A crossover has one end with
the Orange set of wires switched with the Green set
3. Fiber Optic Cable(OFC)
It is a transmission technology that sends
information in the form of pulses of light along specially manufactured optical
fiber at 18600 miles/second (8x103 M/Sec). Each fiber optic consists of a core,
thinner than a human hair, surrounded by a sheath with a much lower refractive
index. Towards its source side is a connector that converts electrical signal
into light waves. Light signals introduced at one end of the cable are
conducted along the cable.
|
 |
4. Microwaves
A method
of radio transmission that uses high frequency waves (in the range of 1-30
Ghtz) to transmit data through space. This is a popular way of transmitting
data since it does not incur the expense of laying cables. Because they can not
bend or pass obstacles like hills, it is necessary that microwave transmission
is in line-of-sight. It requires a repeater station (Microwave Erath
Station/V-SAT) every 20 miles or so because of the obstacles and the curvature
of the earth.
For microwave transmission, both satellites
and the earth stations are used to amplify and retransmit the microwaves to
next or target location. For example, DTH and Cell-Phone Network towers.
What is Wi-Fi?
Short for Wireless Fidelity,
Wi-Fi utilizes one of the IEEE 802.11 wireless standards (802.11a, 802.11b or
802.11n) to achieve a wireless network. In this network “Radio Waves” are used
to establish the link or path between the communicating nodes via a “WiFi
Router”. This type of network, use very much low frequencies that are not used
by networks neither allocated to anybody. The radio waves can be received in
the range of 11-90 meters.
A home wireless network
commonly broadcasts a signal using a WAP (Wireless Application Protocol) to
send and receive signals from wireless devices on the network.
What is Protocol?
Sometimes referred to as an
access method, a protocol is a standard used to define a method of exchanging
data over a computer network such as LAN, Internet, Intranet etc. Each protocol
has its own method of how data is formatted when sent and what to do with it
once receive. Protocols also define a method for compressing data and/or to
check for errors in data.
Some popular communication
protocols are: BISYNC, SDLC, HDLC, NetBIOS, NetBEUI, AppleTalk, TCP/IP, POP,
IMAP, MIME, HTTP and SLIP/PPP etc.
What is BOOTP?
Short for BOOTstrap Protocol,
it allows a client to discover certain network information; for example, to
fetch IP address from DHCP server.
Popular
Communication Protocols
1. IPX/SPX
Short for Internet Packet
eXchange/Sequential Packet eXchange. IPX/SPX is for local-area network only. Used
by NetWare operating system between network clients, applications, and network
peripherals via the physical address.
2. LDAP
Short for Lightweight
Directory Access Protocol, LDAP is an Internet protocol that runs over TCP. It
is used by e-mail programs (e.g., PINE, OutlookExpress) to look up contact
information.
3. Uuencode
Short for Unix-to-Unix
encode, uuencode is a protocol for transmitting any non-plaintext files such as
images and other file attachments in e-mail.
4. MIME
Short for Multipurpose
Internet Mail Extensions. MIME is a standard format, that allows the attachment
(in E-mail) and sending of non-text files, such as compressed files(.zip),
sound files(.wav,MP3), graphic files(.gif,.jpg), document files and video files(.avi,
MPG4, .wmv) etc.
5. NetBIOS
Short for Network Basic
Input/Output System. It allows software applications to communicate with
network hardware, and allow data to be transmitted properly over a network.
6. PPP
Short for Point-to-Point
Protocol, it is a communication protocol that enables a user to utilize their
dialup connection (commonly a modem) to connect to other network protocols like
TCP/IP.
Overview of TCP-IP
TCP/IP is the acronym for Transmission Control Protocol and
Internet Protocol. It is a set of communication protocols designed and
developed by US Dept. of Defense’s (DARPAnet) in late 1970’s. TCP/IP is
originally the WAN protocol suite for the purpose of maintaining communication
links and data transfer between sites over the circuit switching (Telephone)
and packet switching (Computer) networks. TCP/IP is a four layer protocol
software suite which provides following functions:
1. Remote logons
2. File Transfer
3. Electronic Mail
4. Support for distributed windowing system
5.
NEWS
6.
WWW
7.
NFS (Network File System)
|
 |
TCP/IP
Command/Utilities
1. PING
(Packet Internet Groper):
It verifies IP-level connectivity to another
TCP/IP computer by sending ICMP(Internet Control Message Protocol) ‘Echo
Request’ messages.
Ping is used to troubleshoot connectivity,
reach-ability, and name resolution.
Usage:
- C:\>
Ping 192.168.0.1 –t Or
- C:\>
Ping localhost –t Or
- C:\>
Ping www.lan.com –t
2. Tracert:
It determines the path taken to a destination
by sending ICMP ‘Echo Request’ message, to the destination with incrementally
increasing Time to Live (TTL) field values.
3. Ipconfig:
Displays all current TCP/IP network
configuration values (IP Address, Hostname, Physical Address, Subnet Mask and
Default Gateway etc.).
It can refresh DHCP and DNS settings also.
Ipconfig actually display the IP address, subnet mask, and default gateway for
all adapters with no parameters.
Usage:
c:\>ipconfig Or
c:\>ipconfig /all
Note:
IP address and DNS problem can
be solved by running this command as follows:
C:\>
Ipconfig /renew
(to get correct IP address from DHCP server)
C:\>
Ipconfig /flushdns
(to
solve DNS querying problem
4. Finger:
It displays information about
a user or users on a specified remote computer (running UNIX).
5. What is
“APIPA” IP address?
Automatically Provide IP
Address or APIPA is assign to a TCP/IP host machine when no DHCP server is
available.
5.
‘Net’ command line tool
Net share: (Usage:
Net view 192.168.0.1)
Net View: (Usage:
Net view)
Net Send: (Usage:
Net send 192.168.0.1 “Hello!”)
7. Arp:
ARP is defined at the network layer of ISO/OSI.
RARP mean to convert physical address into an IP
address.
Addressing in a Computer Network
1 What is
IP Address?
Communication
in TCP/IP network is based on sending messages back & forth between the
computers and network. The message contains a server and recipients address
known as IP address. TCP/IP based hosts uses 32 bit IP address to uniquely
identify themselves and the network to which they belong. IP address is in an
octet based form such as, [192.108.168.5]
In IP
Address each octet is in the range of 0-255 decimal number. The left-most
one/two/three octet dictates the “class” of a network and the remaining is host
address. As such they are in Class A, Class B, Class C, Class D and Class E.
Example (TCP/IP based LAN)
|
|
|
|
|
2 What is
the MAC address/Physical address?
In computer networking, the
Media Access Control (MAC) address is every bit as important as an IP
address. The MAC address is a unique value associated with a network adapter.
MAC addresses are also known as hardware addresses or physical addresses. They
uniquely identify an adapter (Workstation) on a LAN.
MAC addresses are 12-digit hexadecimal numbers (48 bits in length). By
convention, MAC addresses are usually written as following:
MM:MM:MM:SS:SS:SS
MM-MM-MM-SS-SS-SS
The first half contains the
ID number of the adapter manufacturer, regulated by an Internet standards body.
The second half represents the serial number assigned to the adapter by the
manufacturer. MAC addresses function at the data link layer.
Usage:
1. Novell “NetWare
LAN” based on IPX/SPX communication protocols.
2. DHCP
relies on MAC addresses to manage the unique assignment of IP addresses to
devices.
MAC vs. IP Addressing
MAC Address
|
IP Address
|
1. It is uniquely assigned to Network Adapter.
|
It is uniquely assigned to a machine.
|
2. It exists in Hexadecimal format
|
It exits in Decimal format
|
3. It is 12 Hexadecimal characters and 48 bits lengthy
|
It is 4 set of Octets in the range of 0-255 and 32
bits lengthy
|
4. It works at Data Link layer
|
It works at Network layer
|
5. It is Hardware implementation
|
It is software implementation
|
6. It is fixed to NIC
|
It is not fixed ( dynamic or static)
|
7. Physical address has no network classes
|
IP address has different network classes i.e., Class
A, Class B etc.
|
Network Device
1. NIC: It is the acronym
for Network Interface Card. It is a hardware device used to connect the PC with
another computer e.g., Server, Workstation or any other network device such as
HUB or Switch etc. It is responsible for transmitting and receiving the signal
from network media (cable) in a LAN. The NIC is defined at the physical layer of
ISO/OSI network reference model.
2. Bridge: In networking, a
hardware device used to connect local area network (even networks using
different wiring or network protocols) together so that can exchange data. A
bridge operates at the data-link layer of the ISO/OSI network reference model.
A bridge manages the flow of traffic between the two local area networks by
reading the address of every packet of data that it receives.
3. Router: A router is
similar to a bridge, but maintains a table of pathways in a large WAN. In
networking, an intelligent connecting device that can send packets to the
correct local area network-segment to take them to their destination. Routers
link dissimilar (different protocols
& addressing mechanism) network segments at the network-layer of ISO/OSI
networking reference model.
4. Gateway: In networking, a
Gateway is basically a shared connection between a LAN and a larger system such
a mainframe computer or a large ‘packet switching’ network. It is the
combination of both hardware and software. It is a highly sophisticated and
more advanced computer system. A Gateway is defined at the 'application layer'
of ISO/OSI network reference model. It provides protocol conversion facility to
the networks. It accepts the messages between two different networks then data
is converted as well as reformatted into other network understandable format
and protocol. The messages are forwarded to the final destination network like
a router.
A gateway is a network point
that acts as an entrance to another network. On the Internet, a node or
stopping point can be either a gateway node or a host (end-point) node. Both
the computers of Internet users and the computers that serve pages to users are
host nodes. The computers that control traffic within your company's network or
at your local Internet service provider (ISP) are gateway nodes.
In the network for an
enterprise, a computer server acting as a gateway node is often also acting as
a proxy server and a firewall server. A gateway is often associated with both a
router, which knows where to direct a given packet of data that arrives at the
gateway, and a switch, which furnishes the actual path in and out of the
gateway for a given packet
Examples:- VSNL(TATA), Sify,
Relaince , BSNL and MTNL etc.
5. HUB: A HUB is simply a
device that accepts multiple connections. In a digital network e.g., LAN or WAN
it is the central location as well as central host or controlling and
connecting device between clients and servers. A HUB is either passive (only
accepts connections) or active (monitors and control the flow of signals).
9. Switches:
The LAN Switch Mechanism and
Its Advantages
A LAN switch is a local area
networking device that prevents data packet collision, and maximizes transmission
speed as well as bandwidth allocation. This is a good replacement to a network
hub and solves problems associated with expanding networks.
In a network where a LAN
switch is used, each node gets a direct connection to a switch. That is, a node
gets a dedicated connection to the switch which only it (the node or the
computer) and the switch use. This dedicated connection makes it possible for
one node to maximize use of the bandwidth available to it. After all, no other
node is competing with it for bandwidth. This means speedy data transmission.
Moreover, the connection
between the node and the switch can be made using cabling which has a separate
route for data that the node is sending out and a separate route for data that
the switch is forwarding to the node. This eliminates problems of data
collision.
The LAN switch is especially
a vast improvement over the network hub since it has the ability to “read” the
source and destination node of a data packet and forward the packet only to the
destination node.
Whenever the node transmits
data meant for another node in the local area network, the switch intercepts
the data, determines the destination and forwards the transmission to its
intended destination. Since a data packet does not get broadcasted to
unnecessary segments, network congestion is minimized and network bandwidth is
conserved.
6. Repeater: In networking,
it is used to extend the length of the network transmission medium beyond the
standard cable length. It is also used to move packets from one LAN to another.
It actually amplifies and reduces interference for digital signal before relay.
It is defined at the physical layer of network.
7. MODEM: It is the
abbreviation for modulator and demodulator. It is used to connect a telephone
line with the computer system so that digital signal is converted into analog
and vice versa, for the Dial-Up networking. A modem id defined at the Data-Link
layer of network.
8. Port: A computer system
has many interface devices to connect peripherals. A port is also the interface
device. It is used to connect other communicating devices to CPU, such as the
TERMINAL. A port is of two types: serial (COM1, COM2) or parallel (LPT1, LPT2).
A serial port is used to connect MOUSE or TERMINALS but the parallel port
connects a PRINTER or another PC.
IP
Address Classess
1.Class A IP network/Address:
In this class, the first octet is used for
Network Address and the remaining 3 octets are host (client) address.
Therefore, One Class A network may have 224(8x3)= 1,67,77,216 number of
clients.
10.202.56.0
Network Address Host Address
In this IP Address
class, the first octet is always in the range of 0-127(Practically 1-126). The
first bit of 32-bit IP address is “0”. This type of IP address is used by very
large networks, ISPs and Internet Gateways such as ARPAnet, ANSnet, MILnet,
NFSnet, SuperNet and CompuServ(AOL) etc mostly in USA.
2. Class B IP
Address/Network:
This type of IP
address is used by medium sized wide area networks such as Govt. owned
networks, regional ISPs, large telecommunication organizations and Web Portals
(Companies on Internet). In class B network, first two octets are called
network address and the last two are host address. The first octet is always in
the range of 128-191 (first 2 bits of 32-bit IP address is “10”).
Example IP Address:
135.202.56.02
Network Address Host Address
There are 214(16-2) = 16384 Class B networks
on the Internet. Each Class B network may have 65534 clients.
3. Class C IP address/Network:
A Class C type of IP address is used by the
small network such as LAN, Intranet, a company network, college/university
campus network etc. In this class first three octets are called network address
and last octet is host/client address.
Example IP Address:
213.202.56.02
Network
Address Host Address
One class C network on the Internet may hay
28-2=254 hosts/clients. The First octet is always in the range of 192-223
(first 3 bits of 32-bit IP address is “110”). 224-3= 2097152 is the count of
Class C networks on the Internet.
3. Class D IP Address Network
The first octet is in the range of 224-239.
It is only used by Internet Organization themselves (e.g., IESG, ITF, IAB etc).
This is reserved for some emergency and in restoration of Internet services due
to router and gateway faults (first 4 bits are “1110” in 32-bit IP Address).
4. Class E IP Address
This type of IP Address class is in the range
of 240-247(first 5 bits are “11110” in 32-bit IP Address). It has been reserved
for future Internet problems.
IPv4 – 32-BITS (old) IPv6 – 128 BITS (new)
4
– Octet 16
- Octet
-------------------------------------------
Note: 192.168.0.0
192.168.10.255
Is the IP address pool that is not used and
available to public.
Administrator
This is a built-in user-id in Windows Family
of Operating systems. This user-id created by Windows Setup itself to manage
the PC system. An “Administrator” account has all the rights, permission and
privileges to create or remove or Edit users, groups and sharing as well Install/Uninstall
software or hardware. This user-id is also responsible for “networking” on the
computer system.
Common administrative tasks
·
Backing up and restoring data
·
Changing group memberships
·
Checking event logs
·
Creating administrative scripts
·
Creating logon scripts
·
Creating user and group accounts
·
Deploying and upgrading software
·
Installing a DHCP server
·
Installing a domain controller
·
Managing applications on a local
computer
·
Managing applications remotely
·
Managing directory replication
·
Managing disks and volumes
·
Managing files and folders
·
Managing network printers
·
Managing servers remotely
·
Managing services
·
Monitoring network traffic
·
Monitoring security-related events
·
Monitoring server performance
·
Resetting user passwords
·
Safeguarding your system
·
Scheduling tasks
·
Setting up DNS
·
Setting up TCP/IP
·
Setting user and group security
What is Network Administration?
A computer network is the
collection of computers, servers and other peripheral devices in a business and
organization etc. Administrator is actually the skilled, trained and qualified
person. Who use “Administrator” user-id, to build the computer network in any
environment as LAN, WAN, Intranet and Virtual Private Network (VPN).
In the beginning, servers and
workstations are arranged and setup by a LAN topology such as BUS and STAR.
Then according to the need and requirement of business Operating systems and
Applications are installed and configured either on Server system or at local
host. A network and its resources are then made available to users across the
network with different logins (user-id). Users, network, Domain and devices are
all controlled, run and managed by Administrator on the Network Operating
System (NOS) e. g., Windows Server 2003/2008 or NetWare and Linux etc.
Network administration is
very much responsible and execution of intelligence for better control,
management and running day-to-day business. This task includes many roles,
activities and jobs. Such as:
1.
Creating Groups and group policies
2.
Installing, configuration and
managing Active Directory
3.
Installing, configuration and
managing Domain and DNS
4.
Installing, configuration and
managing Web Sites and FTP sites (IIS
Web Server)
5.
Working on Sharing of Files/Folders
and devices
6.
Solving problems related to
permissions, rights and storage etc.
7.
Setting up Safe and Secure Internet
connection with the help of Proxy Server and Firewall.
8.
Troubleshooting, Preparing and
managing IP addresses, Cable and NIC
9.
Extending LAN through HUB or Switch
10. Knowledge
of UTP and Coaxial cable wiring and tools.
It is plastic connector used
to plug UTP cable wiring in 4 pairs. It is a basic component in computer
networking as ARCNet (Attached Resources Computer Network) and STAR topology.
RJ45 needs at both ends of the UTP cable to insert the media to be connected to
an NIC, Switch or HUB. RJ45 cabling has two methods known as Straight-through
and Cross-over.
BNC
BNC or Bus Network Connection
is the copper device. It enables the coaxial cable to connect to NIC, HUB or
Switch. This device has transceiver capable of transmitting and receiving
digital/analog signal to and fro the media (thin or thick coaxial cable).
Windows Server 2003
Introduction (Overview)
Microsoft Windows 2003
Advanced Server is basically a network operating system (NOS) designed to
setup, configure, manage and to run the Client/Server network based on Windows
platforms ( Windows 2000, Windows XP and Windows Vista). This is very much
similar to other Multiuser operating systems such as LINUX, UNIX and NetWare
etc. Windows 2003 Advanced Server operating system has become popular to setup
the LANs, Intranet and Internet Servers (ISP) as well as Web Servers. This
Operating system is available in following categories:
1. Enterprise Edition
2. Standard Edition
3. Web Edition
4. Datacenter Edition
Windows 2003 Advanced Server
can be confugured in many different
roles, which are as follows:
1. File Server
2. Application Server (IIS)
3. Active Directory (Domain
Controller)
4. Print Server
5. DHCP Server
6. Terminal Server
7. Mail Server
8. Streaming Media Server
What is Active Directory
It is a Windows-based directory service. Active
Directory stores information about objects on a network and makes this
information available to users and network administrators. Active Directory
gives network users access to permitted resources (ftp site, Web site and
printer etc.) anywhere on the network using a single logon process.
It provides network administrators with an
intuitive, hierarchical view of the network and a single point of
administration for all network objects.
DHCP Overview
DHCP is the abbreviation for Dynamic Host
Configuration Protocol. It is a TCP/IP service protocol that offers dynamic
leased configuration of host IP addresses. DHCP provides safe, reliable, and
simple TCP/IP network configuration.It
prevents address conflicts, and helps conserve the use of client IP
addresses on the network.
DHCP uses a client/server model where the DHCP
server maintains centralized management of IP addresses that are used on the
network. DHCP clients request and obtain lease of an IP address as part of
their network boot process.
DHCP
terminology
1. scope: A scope is the
full consecutive range of possible IP addresses for a network. Scopes typically
define a single physical subnet in our network (Class C/B/A).
2. Address pool: In a DHCP
scope, the remaining addresses are eligible for dynamic assignment by the
server to DHCP clients on your network--leaving exclusion ranges.
3. Lease: A lease is a
length of time that a DHCP server specifies, during which a client computer can
use an assigned IP address. When a lease is made to a client, the lease is active.
Before the lease expires, the client typically needs to renew its address lease
assignment with the server. A lease becomes inactive when it expires or is
deleted at the server. The duration for a lease determines when it will expire
and how often the client needs to renew it with the server
0 Comments