1. DATA COMMUNICATION

2. Data Communication Data communication is the transmission of data from one location to the other. Data can be sent in two ways: directly from one device to another. Eg. Bluetooth connections or via a server eg. Networked computers

3. Computer Networks A computer network is a set of computers that are linked together by cables or wirelessly that share information with each other. Computers on the network can: Access the same files held on one server Share resources like a printer or scanner Share files with each other

4. Types of Computer Networks LAN – Local Area Network MAN – Metropolitan Area Network WAN – Wide Area Network

5. LAN (Local Area Network)

6. LAN A local area network is made up of 2 or more computers and or peripherals connected to each other within the same geographical area via cables or wirelessly. Not necessarily in the same building.

7. MAN (Metropolitan Area Network)

8. MAN A network built across a whole town or city. It connects many LANs together and is usually run by one company.

9. WAN (Wide Area Network) Remote connection

10. WAN A network that connects computers over a very wide area across different geographical locations. It uses satellite and other connections other than cables because of the distance. WANs share information across organizations so that files can be accessed from anywhere across the world.

11. Comparison Chart LANMANWAN LocationSame geographical area Stretched across a city Stretched across the world ConnectionCableWireless and the internet. Wireless, The internet and Satellite. BusinessesSmall companiesLarge organizations Multi National Organizations

12. Advantages and Disadvantages ADVANTAGESDISADVANTAGES All information stored on one server for easy access Expensive to set up and may require additional employees to maintain Many users can share files easily across large geographical barriers Network security can be compromised by hackers Easy management of company’s information Easy way of communication via the internet or voice Proper standards maintained across the company

13. Servers File Server Stores files that will be accessed by the whole network in one central location. Print Server Connects a printer to one central location so that everyone can print to it.

14. Modem A device that converts digital signals to analogue and vice versa. Measured in bps (bits per second) Data sent is on wires is analog and needs to be converted to digital so the computer can understand it.