Wednesday, June 11, 2008

ICTL - F2 - 1.2 - Nwork, LANmanWAN



Define Computer Networks

1.0 : Network :
is any method of sharing information between two systems (human or mechanical).
consists of two or more computers that are linked in order to share resources (such as printers and CD-ROMs), exchange files, or allow electronic communications.
The computers on a network may be linked through cables, telephone lines, radio waves, satellites, or infrared light beams.

Define Communications :

transfer of communication from a sender across a distance to a receiver
-What are being transmitted
- electricity, radio waves or light,
information and data in the form of codes
- information such as texts, voice, spund,
video, graphic, images or combination of
any two or more
-what are the medium

Benefits of Computer Networks :

*handle transactions like account management, fund transfer and payment over the internet
*transaction can be done at home or from the office

-Long Distance Communication
*communication via texts, voice pr video
*cost cheaper than normal telephone calls
*decision can be made through video

Conducting bussinness on the internet
Payment is normally via credit card

-On-line Education
Students at any location can participate in an on-line classroom, downloading tutorial questions and submitting assignment

  • Sharing devices
  • Sharing data and information
  • Sharing internet access


  1. Network devices – is any type of hardware capable of transmitting data, instructions and information between a sending and receiving device.
  2. Examples of network devices :
    1. NIC (Network Interface Card)
    2. Wireless Network Interface Card
    3. Internal Modem
    4. External Modem
    5. Hub
    6. Switch
    7. Router
    8. Wireless AP (Access Point)


There are 3 types of computer networks :

LAN (Local Area Network)
MAN (Metropolitan Area Network)
WAN (Wide Area Network)
LAN : covers a small region of space typically a single building, schools or at home.
- limited geographical area
- often share resources such as printers
- often connected via cable

MAN : connects LANs in city or town

- a connection of LANs with the same geographically area for instant a city
- if long distance, use fibre optic cable for best connection

WAN : a collection of LANs or MANs or both. A very large geographical area for instant a country or beyond the border.

- cover a large geographic area
- using a communication channel
- combine any types of media such as telephone lines
- consist of two or more LAN/MAN connected together
- world’s largest WAN is internet

2.0 : INTERNET ?

The Internet, or the Net, is the worldwide, publicly accessible system of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP).

It consists of millions of smaller business, academic, domestic and government networks, which together carry various information and services, such as electronic mail, online chat, and the interlinked Web pages and other documents of the World Wide Web.

Internet is one of the uses of communication. Through the Internet, society has access to global information and instant communication.

Advantages of Internet :

1. Can get more information

2. Can get information faster.

3. No need to spend money to get information.

4. Can get latest news / information.

5. Can complete task easier.

6. Can access information all around the world.

7. Can make long distance communication - text, voice, video communication.

8. Email.

9. Video conferencing.

Disadvantages of Internet :
1. Wasting time
2. Wasting money
3. Internet will make students forget to study
4. Pornography - students are not allow to access
5. Not enough security.
6. Virus can attack any time.
7. Can involve in social problem


  1. Modem (internal / external)
  2. Access account
  3. NIC (Network Interface Card)
  4. Wireless NIC
  5. Hub / Switch
  6. Router
  7. WAP (Wireless Access Point)