Networks

Networks

1. A network is made up of multiple computers/ devices that allows data to be exchanged between the devices

2. Advantages: -Allow data to be exchanged with other computers within the network - Sharing devices suh as printers saves money - Data can be easily backed up - Users can easily communicate with each other through eMail or Instant Messaging

3. Disadvantages: -Expensive to install - Viruses can spread very easily if on one computer within the network - A lot of data can be lost or stolen in the event of hacking - If the server breaks down then no one can access any files within the network - Requires a full time manager to maintain it

4. Hub:

   • Connect many network devices together into a single network segment. Number of input/ output ports that connect to each other. Data transmitted to all computers on the network leading to unnecessary traffic

5. Switch:

   • Similar to a hub but directs network traffic only to the intended recipient and so cuts down on any unnecessary traffic. It does this by building up a table of addresses of computers in the network initially

6. Router:

   • Large ones used over the internet, whereas small ones used at home which connect the individual computers to an ISP. Used to forward data packets between different networks. It reads the destination, and passes it along to a router closer to this destination

7. Network Interface Card

   • Card that goes into a computer to provide a connection to a network. Unique address called a MAC Address. In most new computers it is built in to the Motherboard

8. Wireless Access Point

   • Allows Wireless devices to connect to a wired network. Converts data it receives through cables into a wireless signal and vice versa

9. LAN Vs WAN

   • A Local Area Network is a network located within one site. The infrastructure is usually owned by the organisation that runs the network. E.g. a school network or an office network
   • A Wide Area Network covers large geographical regions. It is built of by numerous LANs that are connected to each other via Telecoms. E.g. the Internt, ATM Network

10. Client- Server Network

    • Server controls the security and has one server that has central security. All clients are dependent on the main server & data can be easily backed up from the server. But, server can be over loaded & be slow if too many clients are using it

11. Peer-to-Peer Network

    • No network wide security in place so up to each user and no one has central command. No dependency at a server. But no central backup and if machines on the network are slow then they will slow down all the other machines