Networks

Networks

1. Topologies

   • Ring
     • A ring network is a peer to peer network because there is no server, all the computers are arranged in a circle
     • Data sent by one computer passes around the ring until it reaches the correct computer
     • Advantages
       • Network is not dependent on a central computer
       • Each computer has the same access as the computers
     • Disadvantages
       • If their is a break in the connection then the whole network fails
   • Bus
     • A bus topology all the devices are connected to the network are connected to a common shared cable called the backbone.
     • The signals are passed in either direction along the backbone
     • Advantages
       • Easy to add extra devices to the network
       • Cost effective because small amount of cable needed
     • Disadvantages
       • if there are more than 12 devices on the network the speed is degraded
       • if there is a break in the backbone cable, then the network cannot be used
   • Star
     • A star topology uses a central connection point to connect all the devices on a network together the central connection point can be aa hub, switch or router
     • Advantages
       • if one of the cables fails then the other can be used
       • extra computers can be added without much loss in performance
     • Disadvantages
       • Higher cost as large amount of cabling needed
       • Dependence on central server or router
   • Peer-to-peer (P2P)
     • A P2P network are networks where each computer has the same status and they are able to communicate with each other on an equal footing
     • Advantages
       • Cost saving as no server needed
       • No network manager needed
       • Easy to set up
       • No reliance on server
     • Disadvantages
       • Backups cannot be made centrally
       • Poorer security
       • Unsuitable for very small networks
   • Client server
     • Advantages
       • Security is better
       • Centralized data
       • Backups are taken centrally
     • Disadvantages
       • More expensive
       • Need specialist knowledge
       • Software is expensive