is a lesson about computer network that is the development EngAbdirahman Hassan Nour of students IT university Golis of Berbera to receive an assignment of the PPT 21Slide...
2. Definition of Computer network
• A Computer network is a collection of computers
and devices Connected together via
communication devices and transmission media.
For example it my connect computers, printers and
scanners.
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3. Definition of Network Communication
• Communication describes a process in
which two or more computer, devices
transfer data, instructions and information.
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4. Advantage of Computer networks
• Sharing of Devices such as printer and
scanner
• Sharing program / software
• Sharing files
• Sharing data
• Sharing information
• Sharing of single high-speed internet
connection
• Better communication using internet
services such as email, mailing list and
internet Relate chat (IRC)
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5. Disadvantage of Computer Network
•
•
•
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The larger network becomes, the more
difficult it is to manage.
If the network stops operating system,
then it may not be possible to access
various resources
Computer Viruses: If any computer
system in a network gets affected
by computer virus, there is a possible
threat of other systems getting affected
too.
8. Local Area Network (LAN)
• A local area network is a network that
connects computers and devices in a limited
geographically area such as a home, school
computer laboratory, office building.
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9. Metropolitan Area Network (MAN)
• Metropolitan Area Network (MAN) is high speed
network that connect local area network in
Metropolitan Area such as city or town and handles
bulk of communication activity across the region.
• A MAN typically includes one or more LAN but covers
a smaller geographically area than a WAN.
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10. Wide Area Network (WAN)
• Wide Area Network is a network that covers a large
geographically area such country or the world
• WAN combines many types of media such as
telephone lines, cables
and radio wave. A WAN
can be one large network
or can consist of two or
more LANs connected
together.
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12. Network Architecture
• Network Architecture is the over all design
of a computer network that describes how a
computer network is configured and what
strategies are being used.
• It also know as network model or network
design.
• Two main network architecture:
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13. Server and Clients
• A network server is a computer designed to
process requests and deliver data to other (client)
computers over a local network or the Internet.
• A Client is a computer that
retrieves information
from or uses resources
provided by a server
or main computer.
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17. Intranet
• An intranet is a private network within an organization
that resembles the internet.
• organizations use intranets to provide information to
their employees.
• typical applications include electronic telephone
directories, email addresses,
employee information,
internal job openings
and much more.
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18. Extranet
• Is a private network that connects more than one
organizations
• many organizations use the internet technologies to allow
suppliers, customers and business partner limited access to
their network
• the purpose is to increase efficiency and reduce costs
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19. Internet
• is a public network
• it is worldwide collection of networks that links million of
business, government agencies, educational institution and
individuals.
• internet users can access service like web browsing, email,
file transfer, mailing list, chat rooms, instant messaging and
newsgroups.
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20. Difference Between Internet, Intranet and
Extranet
Differences
Extranet
Internet
Used for
Private
Private
Public
Types of users
Provide
information for
organization
employees
Provide
information to
suppliers,
customers and
business partner
Provide
information for
public
Usages
Telephone
directories,
internal job
opening,
employee
information
Access data, check
status, place
orders, send email
Access all kinds
of information
Security
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Intranet
High
Use virtual private
network (VPN)
technology to
communication
over the internet
more secure
Loose
Teaching Tip
Figure 9A.2 on page 342 visually describes the sharing process. It can be helpful to have students open a shared file that you control. Make a change then have the students open it again. Alternatively, share a document and allow your students to write in it. Then demonstrate how the shared document changes.
Spend time discussing why application servers need to be so powerful.
Teaching tip
Figure 9A.4 on page 344 shows a print queue. It can be helpful to demonstrate your classroom queue.
Teaching tip
It is fun if you can setup a teleconference in your classroom. Students get to learn how to join or create the conference. Additionally, they learn how to participate. Finally, students have fun, especially with shared whiteboards.
Insider information
The text describes needing special software to back up data from user drives. However, the backup utility that comes with Windows 2000 and XP is capable of performing this chore.
Teaching tip
Use a real world example to describe an organization with interconnected LANs.
Teaching tip
Blockbuster Video uses a WAN to connect it’s stores nationwide. Customers from Pittsburgh may rent videos in Hilton Head. Late fees will even be displayed!
Teaching tip
An example of a regional resource is a supercomputer. For example, Pittsburgh has the Pittsburgh Super Computing center (www.psc.edu). The various colleges in Pittsburgh connect to the center through a MAN in Pittsburgh.
