1.4 | Network | Pt. 2

1.4 | Network | Pt. 2

1. What is a network?

   • A collection of computers, servers, mainframes, network devices, peripherals, or other devices connected to one other to allow the sharing of data.
   • A group of interconnected computers / devices.
   • What are the main types of network?
     • Local Area Network (LAN)
       • What is LAN?
         • It covers a small area such as one site or building.
           • eg. a school
     • Wide Area Network (WAN)
       • What is WAN?
         • It covers a large geographical area.
           • eg. the internet
         • Most are made from several LANs connected together.

2. What are the advantages?

   • Sharing devices saves money.
     • eg. printers
   • Files can be easily shared between users.
   • Data is easy to backup as all the data is stored on the file server.
   • Security is good.
     • Users cannot see other users' files unlike on stand-alone machines.

3. What are the disadvantages?

   • Purchasing the network cabling and file servers can be expensive.
   • Viruses can spread to other computers throughout a computer network.
   • Danger of hacking, particularly with WAN.
     • To prevent this, security procedures are needed.
       • eg. a firewall
   • If there is a lot of data of travelling on a network, it may slow down.

4. What affects the performance of networks?

   • The number of users.
     • Too many users on the same network can cause the network to slow down if there is sufficient bandwidth for the data.
   • Error rate.
     • Less reliable connections increase the number of errors that occur when data is transferred.
   • Transmission Media
     • Connections between computers on a network - wired or wireless.
   • Bandwidth
     • Measures the amount of data that can transfer through a communications channel over a given period of time.
   • Latency
     • The time it takes for components to respond to a request.