1 Objective
2 Overview
3 Basics of computers
3.1 What is a computer?
3.2 Data and information
3.3 Advantages of computers
4 Practice Exercises 1
5 Components of a computer
5.1 Hardware
Input devices
Output Devices
Storage Devices
2 Overview
3 Basics of computers
3.1 What is a computer?
3.2 Data and information
3.3 Advantages of computers
4 Practice Exercises 1
5 Components of a computer
5.1 Hardware
Input devices
Output Devices
Storage Devices
5.2 Software
System Software
System Software
Application Software
6 Practice Exercises 2
7 Operating System
7.1 Objectives of Operating System
7.2 Characteristics of Operating System
7.3 Operating Systems - Layers
8 Practice Exercises 3
9 Networking
9.1 Network Architecture
9.2 Network Applications
9.3 Type Of Computer Networks
10 Computer Network Model
10.1 OSI Model
10.2 Internet Model
11 Practice Exercises 4
7.1 Objectives of Operating System
7.2 Characteristics of Operating System
7.3 Operating Systems - Layers
8 Practice Exercises 3
9 Networking
9.1 Network Architecture
9.2 Network Applications
9.3 Type Of Computer Networks
10 Computer Network Model
10.1 OSI Model
10.2 Internet Model
11 Practice Exercises 4
At the
end of the session, participants will learn to
• explain the basic organization of a computer
system
• explain different types of input and output
devices
• define software and its classification
• distinguish between system software and
application software
In this
lesson we present an overview of the basic design of a computer system. How the
different parts of a computer system are organized and various operations
performed to perform a specific task. Computer components are divided into two
major categories namely hardware and software. In this lesson we will discuss
about hardware, i.e., the machine itself and its connected devices such as
monitor, keyboard, mouse etc., as well as software that makes use of hardware
for performing various functions.
A
computer is an electronic device that stores and processes data. A computer
includes both hardware and software. In general, hardware is the physical
aspect of the computer that can be seen, and software is the invisible
instructions that control the hardware and make it work.
Computer
programming consists of writing instructions for computers to perform. You can
learn a programming language without knowing computer hardware, but you will be
better able to understand the effect of the instructions in the program if you
do. This section gives a brief introduction to computer hardware components and
their functionality.
The computer performs basically
five major operations of functions irrespective of their size and make. These
are:
1. it accepts data or instruction by way of input
2. it stores data
3. it can process data as required by the user
4. it gives results in the form of output
5. it controls all operations inside a computer
We discuss below each of these
operations.
Input
is the process of entering data and programs
into the computer system.
Control
Unit (CU) The process of input, output, processing and
storage is performed under the supervision of a unit called ‘Control Unit’. It
decides when to start receiving data, when to stop it, where to store data,
etc. It takes care of step-by-step processing of all operations inside the
computer.
Memory
Unit is used to store data and instructions.
Arithmetic
Logic Unit (ALU) The major operations performed by the ALU are
addition, subtraction,multiplication, division, logic and comparison.
Output
is the process of producing results from the
data for getting useful information.
The ALU
and the CU of a computer system are jointly known as the central processing
unit (CPU). You may call CPU as the brain of any computer system.
Data can be defined
as a representation of facts, concepts or instructions in a formalized manner
which should be suitable for communication, interpretation, or processing by
human or electronic machine.
Data is represented with the help of characters like
alphabets (A-Z,a-z), digits (0-9) or special characters(+,-,/,*,<,>,=
etc.).
Information
is organised or classified data which has some
meaningful values for the receiver. Information is the processed data on which
decisions and actions are based.
Data
processing is the re-structuring or re-ordering of data
by people or machines to increase their usefulness and add values for
particular purpose. Data processing consists of three basic steps: input,
processing and output. These three steps constitute the data processing cycle.
High
speed Computers have the ability to
perform routine tasks at a greater speed than human beings. They can perform
millions of calculations in seconds.
Accuracy
Computers are used to perform tasks in a way
that ensures accuracy.
Storage
Computers can store large amount of
information. Any item of data or any instruction stored in the memory can be
retrieved by the computer at lightning speeds.
Automation
Computers can be instructed to perform complex
tasks automatically ( which increases the productivity).
Diligence
Computers can perform the same task repeatedly
with the same accuracy without getting tired.
Versatility
Computers are flexible to perform both simple
and complex tasks.
Cost effectiveness
Computers reduce the amount of paper work and
human effort, thereby reducing costs.
1. A computer is an __________________ that
stores and processes data.
2. ____________ is data that has been organized
or presented in a meaningful way.
3. _____________________ is the heart of the
computer and this is where all the computing is done.
4. CPU stands for ___________________________.
5. List any three advantages of computers.
______________________________________________.
Hardware
represents the physical and tangible components of a computer i.e. the
components that can be seen and touched. Examples of Hardware are following:
The
devices which are used to input the data and the programs in the computer are
known as "Input Devices". Input device can read data and convert them
to a form that a computer can use.
Keyboard
is used in the input phase of a computer-based
information system. Keyboard is the most common input device used today. The
data and instructions are input by typing on the keyboard. The message typed on
the keyboard reaches the memory unit of a computer. It’s connected to a
computer via a cable. Apart from alphabet and numeral keys, it has other
function keys for performing different functions.
Mouse
it’s a pointing device. The mouse is rolled
over the mouse pad, which in turn controls the movement of the cursor in the
screen. We can click, double click or drag the mouse. Most mouses have a ball
beneath them, which rotates when the mouse in moved. The ball has 2 wheels on the
sides, which in turn move with the movement of the ball. The sensor notifies
the speed of its movements to the computer, which in turn moves the
cursor/pointer on the screen.
Light
Pen This is an input device which is used to draw
lines or figures on a computer screen. It’s touched to the CRT screen where it
can detect the raster on the screen as it passes.
Scanner
Scanners are used to enter information
directly into the computer’s memory. This device works like a Xerox machine.
The scanner converts any type of printed or written information including
photographs into digital pulses, which can be manipulated by the computer.
Bar
Code Reader This device reads bar codes and coverts them
into electric pulses to be processed by a computer. A bar code is nothing but
data coded in the form of light and dark bars.
Joystick
This device is well known with young people as
it is mainly used for playing computer games. As the name implies, it is like a
stick connected to a platform, which can be moved in all directions. These
movements in turn will move something on screen depending on the game. Usually
joysticks have buttons also called triggers.
Output devices return processed
data that is information, back to the user. Some of the commonly used output
devices are:
Monitor
is perhaps the most important output device
because people interact with this device most intensively than others. Computer
information is displayed, visually with a video adapter card and monitor.
Information processed within the CPU, that needs to be visually displayed, is
sent to a video adapter. The video adapter converts information from the format
used, in the same manner as a television displays information sent to it by a
cable service.
Printer
After a document is created on the computer,
it can be sent to a printer for a hard copy (printout). Some printers offer
special features such as colored and large page formats. Some of the most
commonly used printers are:
Laser
printer produces high quality print that one normally
finds in publishing. It is extremely fast and quiet.
Ink-jet
printer creates an image directly on paper by spraying
ink through as many as 64 tiny nozzles. Although the image it produces is not
generally quite as sharp as the output of a laser printer, the quality of
ink-jet images is still high.
Dot
matrix printer was very popular at
one point of time. It is a very versatile and inexpensive output device. In dot
matrix printer the print head physically "hits" the paper through the
ribbon and produces text (or images) by combinations of dots, hence the name
dot matrix printer. Its speed is measured in characters per second (CPS).
Although it is less expensive, it is louder, slower and produces lower print
quality.
Line
printer is generally used with large computer systems
to produce text based data processing reports. Line printers are high-speed
printers with speeds ranging anywhere from 100 to about 3800 lines per minute.
In the past, print quality on line printers was not high. Developments in
technology are improving the print quality on line printers.
Plotter
is a special kind of output device that, like
a printer, produces images on paper, but does so in a different way. Plotters
are designed to produce large drawings or images, such as construction plans
for buildings or blueprints for mechanical objects. A plotter can be connected
to the port normally used by a printer.
Speakers
are another type of output device, which allow
you to listen to voice like music, and conversation with people.
A storage device is any hardware
capable of holding information either temporarily or permanently.
Hard
disk drive (sometimes abbreviated as
Hard drive, HD, or HDD) is a device used to permanently store and also retrieve
information. There are many variations, but their sizes are generally 3.5"
and 2.5" for desktop and laptop computers respectively. A hard drive
consists of one or more platters to which data is written using a magnetic
head, all inside of an air-sealed casing.
USB
flash drive, data stick, pen drive,
memory unit, key chain drive and thumb drive, a jump drive is a portable
storage device. It is often the size of a human thumb (hence the name) and it
connects to a computer via USB port. Today, flash drives are available in sizes
such as 256MB, 512MB, 1GB, 5GB, and 16GB and are an easy way to transfer and
store information.
DVD Digital Versatile Disc-Recordable, DVD is a drive
capable of recording once to a disc and reading many times after it has been
created.
As you
are aware, a computer cannot do anything on its own. It is the user who
instructs the computer; what to do, how to do and when to do. In order to
perform any task, you have to give a set of instructions in a particular
sequence to the computer. These sets of instructions are called programs.
Software refers to a set of programs that makes the hardware perform a
particular set of tasks in particular order.
When you
switch on the computer the programs stored in ROM are executed which activates
different units of your computer and makes it ready for you to work on it. This
set of programs can be called system software.
System
softwares are sets of programs, responsible for running the computer,
controlling various operations of computer systems and management of computer
resources. Operating System (OS) falls under this category. we will learn more
about operating system in further sessions.
Application software is a set of
programs, which are written to perform specific tasks, for example: An
application package for managing a library known as library information system
is used to manage information of the library such as: keeping book details, account
holder details, book issue details, book return details etc. Another
application package for managing student details is called student’s
information system, manages student’s roll no, name, parent’s name, address,
class, section, processing of examination results etc. Application software can
be broadly classified into two types:
• Generalized Packages
• Customized Packages
Generalized
Packages are user friendly softwares
written to cater to user’s very general needs such as preparing documents,
drawing pictures, database to manage data/information, preparing presentations,
play games etc. It is a group of programs that provide general purpose tools to
solve specific problems. Some of the generalized packages are listed below:
Word
Processing Software (for preparing documents) - Word Perfect, MS-Word, OpenOffice.org Writer
Spreadsheets
(Data Analysis) - Lotus Smart suites,
MSExcel,OpenOffice.org Calc, Apple Numbers
Presentations
(Presentation Graphics) - MS-PowerPoint,OpenOffice.org Impress
Database
Management System - MS-Access,
OpenOffice.org Base, MS-SQL Server, ORACLE
Graphics
Tools - Paint shop pro, Adobe
Photoshop
Customized
Packages are the applications that
are customized (or developed) to meet the specific requirements of an
organization/institution. For Example: Student information details, Payroll
packages, inventory control etc. These packages are developed using high-level
computer language.
1. All of the following are examples of input
devices except
A. Scanner
B. Mouse C. Printer D. Keyboard
2. Which of the following stores more data?
A. DVD
B. CD ROM C. Floppy Disk
3. Java is
A. an Operating System B. a Compiler
C. an Input Device D. a Programming Language
4. DVD stands for
______________________________________________.
5. List any two type of printers.
_______________________________________.
6. The _______________ device reads bar codes and
coverts them into electric pulses to be processed by a computer.
An operating system is a program
that acts as an interface between the software and the computer hardware. It is
an integrated set of specialised programs that are used to manage overall
resources and operations of the computer. It is specialised software that
controls and monitors the execution of all other programs that reside in the
computer, including application programs and other system software.
• To make a computer system convenient to use
in an efficient manner
• To hide the details of the hardware resources
from the users
• To provide users a convenient interface to
use the computer system
• To act as an intermediary between the
hardware and its users and making it easier for the users to access and use
other resources
• To manage the resources of a computer system
• To keep track of who is using which
resource, granting resource requests, according to resource using and mediating
conflicting requests from different programs and users
• To provide efficient and fair sharing of
resources among users and programs
Memory
Management – keeps track of primary memory i.e. what part
of it is in use by whom, what part is not in use etc., and allocates the memory
when a process or program requests it.
Processor
Management – allocates the processor (CPU) to a process
and deallocates processor when it is no longer required.
Device
Management – keeps track of all devices. This is also
called I/O controller that decides which process gets the device, when, and for
how much time.
File
Management – allocates and de-allocates the resources and
decides who gets the resources.
Security
– prevents unauthorized access to programs and
data by means of passwords and similar other techniques.
Job
accounting – keeps track of time and resources used by
various jobs and/or users.
Control
over system performance – records delays between request for a service
and from the system.
Interaction
with the operators – The interaction may take place via the
console of the computer in the form of instructions. Operating System
acknowledges the same, does the corresponding action and informs the operation
by a display screen.
Error-detecting
aids – Production of dumps, traces, error messages
and other debugging and error detecting methods.
Coordination
between other software and users – Coordination and assignment of compilers,
interpreters, assemblers and other software to the various users of the
computer systems.
The structure of OS consists of 4
layers:
Hardware consists of CPU, Main memory, I/O Devices, etc.
Software
(Operating System) includes process
management, memory management, I/O control and file management.
System
programs layer consists of compilers,
assemblers, linker etc.
Application
programs is dependent on user’s need.
Eg. Railway reservation system, Bank database management etc.
7.4 Types of Operating Systems
Within the broad family of
operating systems, there are generally four types, categorized based on the types
of computers they control and the sort of applications they support. The
categories are:
Real-time
operating system (RTOS) - Real-time operating systems are used to
control machinery, scientific instruments and industrial systems. An RTOS
typically has very little user-interface capability, and no end-user utilities,
since the system will be a "sealed box" when delivered for use. A
very important part of an RTOS is managing the resources of the computer so
that a particular operation executes in precisely the same amount of time,
every time it occurs. In a complex machine, having a part move more quickly
just because system resources are available may be just as catastrophic as
having it not move at all because the system is busy.
Single-user
single task - As the name implies, this operating system
is designed to manage the computer so that one user can effectively do one
thing at a time. The Palm OS for palm handheld computers is a good example of a
modern single-user, single-task operating system.
Single-user
multi-tasking - This is the type of operating system most
people use on their desktop and laptop computers today. Microsoft’s Windows and
Apple’s MacOS platforms are both examples of operating systems that will let a
single user have several programs in operation at the same time. For example,
it’s entirely possible for a Windows user to be writing a note in a word
processor while downloading a file from the Internet while printing the text of
an e-mail message.
Multi-user
- A multi-user operating system allows many
different users to take advantage of the computer’s resources simultaneously.
The operating system must make sure that the requirements of the various users
are balanced, and that each of the programs they are using has sufficient and
separate resources so that a problem with one user doesn’t affect the entire
community of users. Unix, VMS and mainframe operating systems, such as MVS, are
examples of multi-user operating systems.
1. ___________________ controls the way in which
the computer system functions and provides a means by which users can interact
with the computer.
2. The operating system is the most common type
of ____________ software.
3. Word processing, spreadsheet, and
photo-editing are examples of
A. Application software. B. System software.
C. Operating system software. D. Platform software.
4. The set of instructions that tells the
computer what to do is
A. Softcopy B. Software C. Hardware D. Hardcopy
5. The Operating System Manages
A. Processes
B. Memory
C. Disks and I/O devices
D. All of the above
6. The operating system does all of the following
EXCEPT
A. Provide a way for the user to interact with
the computer.
B. Manage the central processing unit (CPU).
C. Manage memory and storage.
D. Enable users to perform a specific task
such as document editing.
7. Multiprocessing supports more then one
________ at the same time.
A. User
B. Process C. Hardware D. None of these.
8. ____________ is the ability of an operating
system to control the activities of multiple programs at the same time.
A. Streamlining B. Multiuser C. Multitasking D. Simulcasting
A system of interconnected computers
and computerized peripherals such as printers is called computer network. This
interconnection among computers facilitates information sharing among them.
Computers may connect to each other by either wired or wireless media.
Computer networks can be
discriminated into various types such as Client-Server, peer-to-peer or hybrid,
depending upon its architecture.
• There can be one or more systems acting as
Server. Other being Client, requests the Server to serve requests. Server takes
and processes request on behalf of Clients.
• Two systems can be connected Point-to-Point,
or in back-to-back fashion. They both reside at the same level and are called
peers.
• There can be hybrid network which involves
network architecture of both the above types.
Computer systems and peripherals
are connected to form a network. They provide numerous advantages:
• Resource sharing such as printers and
storage devices
• Exchange of information by means of e-mails and
FTP
• Information sharing by using Web or Internet
• Interaction with other users using dynamic
web pages
• Video conferences
• Parallel computing
• Instant messaging
Generally, networks are
distinguished based on their geographical span. A network can be as small as
distance between your mobile phone and its Bluetooth headphone and as large as
the internet itself, covering the whole geographical world.
Personal
Area Network (PAN) is the smallest
network which is very personal to a user. This may include Bluetooth enabled
devices or infra-red enabled devices. PAN has connectivity range up to 10
meters. PAN may include wireless computer keyboard and mouse, Bluetooth enabled
headphones, wireless printers, and TV remotes. For example, Piconet is
Bluetooth-enabled Personal Area Network which may contain up to 8 devices
connected together in a master-slave fashion.
Local
Area Network (LAN) A computer network
spanned inside a building and operated under single administrative system is
generally termed as Local Area Network (LAN). Usually, LAN covers an
organization’s offices, schools, colleges or universities. Number of systems
connected in LAN may vary from as least as two to as much as 16 million.
LAN provides a useful way of sharing the resources
between end users. The resources such as printers, file servers, scanners, and
internet are easily sharable among computers.
LANs are composed of inexpensive networking and routing
equipment. It may contains local servers serving file storage and other locally
shared applications. It operates on private IP addresses and does not involve
heavy routing. LAN works under its own local domain and controlled centrally.
LAN uses either Ethernet or Token-ring technology. Ethernet is the most widely
employed LAN technology and uses Star topology, while Token-ring is rarely
seen. LAN can be wired, wireless, or in both forms at once.
Metropolitan
Area Network (MAN) generally expands
throughout a city such as cable TV network. It can be in the form of Ethernet,
Token-ring, ATM, or Fiber Distributed Data Interface (FDDI). Metro Ethernet is
a service which is provided by ISPs. This service enables its users to expand
their Local Area Networks. For example, MAN can help an organization to connect
all of its offices in a city.
Backbone of MAN is high-capacity and high-speed fiber
optics. MAN works in between Local Area Network and Wide Area Network. MAN
provides uplink for LANs to WANs or internet.
Wide
Area Network (WAN) covers a wide area which may span across
provinces and even a whole country. Generally, telecommunication networks are
Wide Area Network. These networks provide connectivity to MANs and LANs. Since
they are equipped with very high speed backbone, WANs use very expensive
network equipment.
9.3 Computer Network Topologies
A Network Topology is the
arrangement with which computer systems or network devices are connected to
each other. Topologies may define both physical and logical aspect of the
network. Both logical and physical topologies could be same or different in a
same network.
Point-to-Point
networks contain exactly two hosts such as
computer, switches, routers, or servers connected back-to-back using a single
piece of cable. Often, the receiving end of one host is connected to sending
end of the other and vice versa. If the hosts are connected point-to-point
logically, they may have multiple intermediate devices. But the end hosts are
unaware of the underlying network and see each other as if they are connected
directly.
Bus
Topology all devices share a single communication line
or cable. Bus topology may have problem while multiple hosts sending data at
the same time. Therefore, Bus topology either uses CSMA/CD technology or
recognizes one host as Bus Master to solve the issue. It is one of the simple
forms of networking where a failure of a device does not affect the other
devices. But failure of the shared communication line can make all other
devices stop functioning.
Both ends of the shared channel have line terminator. The
data is sent in only one direction and as soon as it reaches the extreme end,
the terminator removes the data from the line.
Star
Topology All hosts in Star topology are connected to a
central device, known as hub device, using a point-to-point connection. That
is, there exists a point-to-point connection between hosts and hub. The hub
device can be any of the following:
• Layer-1 device such as hub or repeater
• Layer-2 device such as switch or bridge
• Layer-3 device such as router or gateway
As in Bus topology, hub acts as single point of failure. If
hub fails, connectivity of all hosts to all other hosts fails. Every communication
between hosts takes place through only the hub. Star topology is not expensive since
to connect one more host, only one cable is required and configuration is
simple.
Ring
Topology each host machine connects to exactly two
other machines, creating a circular network structure. When one host tries to
communicate or send message to a host which is not adjacent to it, the data
travels through all intermediate hosts. To connect one more host in the
existing structure, the administrator may need only one more extra cable.
Failure of any host results in failure of the whole ring. Thus, every
connection in the ring is a point of failure. There are methods which employ
one more backup ring.
Mesh
Topology In this type of topology, a host is connected
to one or multiple hosts. This topology has hosts in point-to-point connection
with every other host or may also have hosts which are in point-to-point
connection with few hosts only. Hosts in Mesh topology also work as relay for
other hosts which do not have direct point-to-point links. Mesh technology
comes in two types:
• Full Mesh: All hosts have a point-to-point
connection to every other host in the network. Thus for every new host n(n-1)/2
connections are required. It provides the most reliable network structure among
all network topologies.
• Partially Mesh: Not all hosts have
point-to-point connection to every other host. Hosts connect to each other in
some arbitarary fashion. This topology exists where we need to provide
reliability to some hosts out of all.
Tree
Topology Also known as Hierarchical Topology, this is
the most common form of network topology in use presently. This topology
imitates as extended Star topology and inherits properties of Bus topology.
This topology divides the network into multiple
levels/layers of network. Mainly in LANs, a network is bifurcated into three types
of network devices. The lowermost is access-layer where computers are attached.
The middle layer is known as distribution layer, which works as mediator
between upper layer and lower layer. The highest layer is known as core layer,
and is central point of the network, i.e. root of the tree from which all nodes
fork.
All neighboring hosts have point-to-point connection
between them. Similar to Bus topology, if the root goes down, then the entire
network suffers even though it is not the single point of failure. Every
connection serves as point of failure, failing of which divides the network
into unreachable segment.
Hybrid
Topology A network structure whose design contains more
than one topology is said to be hybrid topology. Hybrid topology inherits
merits and demerits of all the incorporating topologies.
The combining topologies may contain attributes of Star,
Ring, Bus, and Daisy-chain topologies. Most WANs are connected by means of
Dual-Ring topology and networks connected to them are mostly Star topology
networks. Internet is the best example of largest Hybrid topology.
Network engineering is a
complicated task, which involves software, firmware, chip level engineering,
hardware, and electric pulses. To ease network engineering, the whole
networking concept is divided into multiple layers. Each layer is involved in
some particular task and is independent of all other layers. But as a whole,
almost all networking tasks depend on all of these layers. Layers share data
between them and they depend on each other only to take input and send output.
In layered architecture of Network
Model, one whole network process is divided into small tasks. Each small task
is then assigned to a particular layer which works dedicatedly to process the
task only. Every layer does only specific work.
In layered communication system,
one layer of a host deals with the task done by or to be done by its peer layer
at the same level on the remote host. The task is either initiated by layer at
the lowest level or at the top most level. If the task is initiated by the
topmost layer, it is passed on to the layer below it for further processing.
The lower layer does the same thing, it processes the task and passes on to the
lower layer. If the task is initiated by the lowermost layer, then the reverse
path is taken.
Open System Interconnect is an open
standard for all communication systems. OSI model is established by
International Standard Organization (ISO). This model has seven layers:
Application
Layer is responsible for providing interface to the
application user. This layer encompasses protocols which directly interact with
the user.
Presentation
Layer defines how data in the native format of
remote host should be presented in the native format of host.
Session
Layer maintains sessions between remote hosts. For
example, once user/password authentication is done, the remote host maintains
this session for a while and does not ask for authentication again in that time
span.
Transport
Layer is responsible for end-to-end delivery between
hosts.
Network
Layer is responsible for address assignment and
uniquely addressing hosts in a network.
Data Link
Layer is responsible for reading and writing data
from and onto the line. Link errors are detected at this layer.
Physical
Layer defines the hardware, cabling, wiring, power
output, pulse rate etc.
Internet uses TCP/IP protocol
suite, also known as Internet suite. This defines Internet Model which contains
four layered architecture. OSI Model is general communication model but
Internet Model is what the internet uses for all its communication. The
internet is independent of its underlying network architecture so is its Model.
This model has the following layers:
Application
Layer defines the protocol which enables user to
interact with the network. For example, FTP, HTTP etc.
Transport
Layer defines how data should flow between hosts.
Major protocol at this layer is Transmission Control Protocol (TCP). This layer
ensures data delivered between hosts is in-order and is responsible for
end-to-end delivery.
Internet
Layer Internet Protocol (IP) works on this layer.
This layer facilitates host addressing and recognition. This layer defines
routing.
Link
Layer provides mechanism of sending and receiving
actual data. Unlike its OSI Model counterpart, this layer is independent of
underlying network architecture and hardware.
1. ‘LAN’ means ____________________________.
2. Servers are computers that provide resources
to other computers connected to a ________________.
3. _____________________ covers a wide area which
may span across provinces and even a whole country.
4. In OSI model _____________________ is
responsible for end-to-end delivery between hosts.
5. IP stands for _____________________.
6. Personal computers can be connected together
to form a
A. Server
B. Network C.
Supercomputer D. Enterprise
7. The process of transferring files from a
computer on the Internet to your computer is called
A. Uploading B. Forwarding C. FTP
D. Downloading
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