1. Networks

2. What is a computer network? A network is two or more computers that are linked together so that they are able to share resources.

3. Networks Shared resources include Hardware – printers, scanners, storage, etc. Software – need only be installed on one computer. Data (e.g. database files). An Internet connection.

4. Networks LANs and WANs Local area networks: Confined to a small area. Usually located in a single building. Use cable, wireless, infrared and microwave links that are usually owned by the organization. Cheap to build. Cheap to run. Wide area networks: Cover a wide geographical area (i.e., between cities, countries and even continents). In lots of different buildings and cities, countries, etc. Use more expensive telecommunication links that are supplied by telecom companies. Expensive to build. Expensive to run.

5. Networks An ICT network consists of Hardware/communication devices Network software Data transfer media

6. Networks Communication devices A network interface card: prepares data for sending over the network sends the data controls the flow of data.

7. Networks Communication devices A hub: is used to join computers in a network allows the connection of cables allows the sharing of files and Internet access

8. Networks Communication devices A switch: is similar to a hub but more intelligent can look at a packet of data to decide where it should go reduces the number of packets of data on a network, which speeds it up

9. Networks Communication devices A router: can be wired or wireless is used to join several networks together is often used to connect several computers in the home to the Internet

10. Networks Network software Network software consists of: Network operating systems – specialist operating systems designed specifically for networks. Network management software – used to help a network manager run a network by keeping track of software, keeping software up-to-date, installing software security patches, helping to manage the help-desk, etc.

11. Networks Data transfer media The medium/method by which the data is transferred in a network can be: metal wire fibre optic cable wireless.