A network allows connected devices like computers and printers to share information and resources. It has components like network interface cards, hubs, and cables. There are three main types of networks: local area networks (LANs) cover a small area like a home or office; metropolitan area networks (MANs) span a city; and wide area networks (WANs) connect LANs over a larger geographic area or globally. The Internet is the largest global WAN that facilitates communication services between devices worldwide. An intranet is a private network internal to an organization that functions similarly to the Internet but is only accessible by those within the organization.

1. Objectives Identify the components of a network State the difference between a local area network (LAN) and a wide area network (WAN) State that computers in a network can share information and resources such as documents, databases, software and Printers State that computers in different locations in the world are linked together to form a global network — the Internet

2. 2.1 What is a Network? Simple Definition: It is where computers or devices exchange data with one another. Another definition: It is any collection of independent computers or devices that communicate with one another over a shared network medium.

3. 2.2 Components of a Network? A network is simply a group of devices that are inter-connected. Some examples of these devices are: • Computers • Scanners • Printers • Modems

4. 2.2 Components of a Network? The function of a network is to pass information between devices that are connected. The network may be formed by using: • Copper cables • Radio waves • Fibre-optic cables • Infra-red rays Share printers and servers Share resources Share files and documents Share information E-mail, chat Communicate Examples Purpose

5. 2.2 Components of a Network? Network Interface Cards It provides a connection between the network cable and the computer. There are also other types of devices that your computer uses to connect to a network. E.g. USB (Universal Serial Bus) modem, or a USB wireless network device. Network Interface Card USB modem USB wireless network device

6. Hub 2.2 Components of a Network? The hub plays a role in connecting different computers together. All members of the network share the same media to transmit data onto a single network. This means that each member will only get a percentage of the available network bandwidth. Bandwidth is the maximum amount of data that can be transmitted along a channel in one second. hub

7. 2.2 Components of a Network? Cables Network cables are used to connect the computers and devices together. These cables carry the data that is sent in the network. Cables

8. 2.3 Types of Networks Local Area Network (LAN) Usually confined to a small geographical area Can be small (linking as few as 3 computers) or large (linking as many as a hundred computers) Metropolitan Area Network (MAN) Connects 2 or more LANs Usually covers an entire metropolitan area (E.g. a large city and its suburbs) Wide Area Network (WAN) Connects multiple LANs and MANs that are located in different places WANs can be created by connecting different LANs and MANs using data services (E.g. leased phone lines, dial-up phone lines, etc.)

9. 2.2 The Internet Definition: It is a system of networks that are linked worldwide and facilitate data and communication services. Examples of communication services include file transfer, electronic mail (E-mail) and World Wide Web. Internet

10. 2.2 The Internet Definition: It is a network that contains Internet-type tools, but available only within an organisation. Intranet

11. A network allows computers or devices to exchange data with one another. LAN, MAN, WAN

12. The Internet is a system of networks that is linked worldwide and facilitates data communication services Requires data services to connect Does not matter Very large area WAN - Does not matter Large area MAN - Does not matter Small area LAN Other difference Number of users Geographical area 3.

13. A network is a collection of devices used to share information and resources. There are 3 type of network: Local Area Network (LAN), Metreopolitan Area (MAN) and Wide Area Network (WAN). The Internet is a network of computers at different locations around the world. An intranet is a computer network within an organisation. It is like an internal Internet. Summary