Chapter

NETWORK Chapter 5 2

What is a Network? *A network is a group of connected computers that allows people to share information. For example, instead of linking each computer to its own printer, all computers can be linked to a common printer for shared access by multiple users 3

Types of Networks The three basic types of networks include: 1-Local Area Network (LAN). 2-Metropolitan Area Network (MAN). 3-Wide Area Network (WAN) 4

1-Local Area Network (LAN) - Network in limited geographical area such as home or office building - LAN covers a small region of space typically a single building, schools or at home - Rarely are LAN computers more than a mile apart. 5

2-Metropolitan Area Network (MAN) -A collection of LANs with the same geographically area for instant a city. -It covers larger geographic areas, such as cities or school districts. -local libraries and government agencies often use a MAN to connect to citizens and private industries. 6

3-Wide Area Network (WAN) -Wide Area Networks (WANs) connect larger geographic areas, such as bank branches or the world. - Dedicated transoceanic cabling or satellite uplinks may be used to connect this type of network. - Can be a collection of LANs or MANs or the mix of two with a very large geographical area for instant a country or even beyond the border. -The best known WAN is the internet 7

Differentiate between the three types of computer networks 8

(Question & Answer session) Network 1. Collection of computers and devices connected via communications devices and transmission media 2. Network in limited geographical area such as home or office building. 3. Connects LANs in city or town 4. Network that covers large geographic area using many types of media 5. What is the world’s` largest WAN ? LAN MAN WAN Internet

INTERNET Chapter 6 10

What is the Internet ? -The internet is a communication system that allows computers around the world to communicate and exchange of the data with each other. -The Internet, also called the Net, is an international network that connects many thousands of networks and millions of computers across the world. Used by many people and organizations to communicate and share information, the Internet links computers of different sizes and types. 11

The short history of the internet -The internet started at 1969 it was called (ARPANET) which is the Advanced Research Projects Agency. -The goal was to allow scientists at different to actions to share information.Also to function if part of the internet was disabled. -The internet started with four nodes in 1969,and became 1000 nodes in 1984, nowadays more than 200 million nodes in the internet. 12

Connection to the Internet There are two main methods to connect to the internet: 1- Slow speed technology : Which is ( dial up access modem) in your computer uses a standard telephone line. 2-High speed connection : Which is the (digital subscriber line(DSL)cable telephone internet services modem, or through wireless or satellite modems. The connection is always running. 13

World Wide Web (WWW) - World Wide Web (WWW) : is a Collection of electronic elements (documents). - Each document is called a web page, which can contain text,graphics,sound,video, and more. 14

Web browser Web browser : is a program that allow users to view web pages. Example: -Microsoft Internet explorer. -Opera -Firefox -Chrome -Safari 15

Internet services Newsgroups. 3-Telnet. 4-Distance Learning 5-Banking services of transfer and bill payment 6-E-library 7-E-commerce 16