Network Topologies

Network Topologies

1. The Ring Topology

   • It is a ring network as it 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 others so no one computer can hog the network
   • Disadvantages
     • if there is a break in the connection then the whole network will fail
     • Faults are difficult to locate
     • it is impossible to keep the network running whilst equipment is added or removed because there is only one path for the data to follow

2. The Bus topology

   • All devices connected to the network are connected to a common shared cable called the backbone. signals are passed in either direction along the backbone
   • Advantages
     • Cost effective because of the small amount of cable needed
     • simple cable runs makes it easy to install
     • easy to add extra devices to the network
   • Disadvantages
     • If there is a braek in the backbone cable then the network can be used
     • if more than about 12 devices are connected to the network then the performance of the network is degraded

3. The star topology

   • it uses a central connection point to connect all the devices on the network together. the central connection point can be a hub a switch or a router
   • Advantages
     • fault tolerance- if one of the cables fails then the other computers can still be used
     • load tolerance- extra computers can be added without much loss in performance because all computers have their own path to the hub
     • easy to add extra computers - extra computers can be added without disrupting the network
   • Disadvantages
     • higher cost - the large amount of cabling needed makes it a more expensive topology
     • dependence on the central hub, switch or router - if the device at the center of the network fails then the whole network will fail.

4. Wireless networks

   • computers can connect to the internet and communicate with other computers in a local area network wirelessly
   • Wireless networks allow people to connect to the internet wirelessly where they can work anywhere with a radio signal
   • Can be used on portable devices
   • WIFI is the hotspots that allow you to access the internet
   • To set up wifi you need:
     • A broadband connection to the internet
     • A router
     • WIFI enabled computers
     • can buy wireless adapters
     • How wifi works
       • Router is connected to the internet by high speed broadband connection
       • Router receives data from the internet
       • It transmits the data as a radio signal using an antenna
       • Computers wireless adapter picks up the signal and turns the radio signal into data that the computer can understand
       • Wifi
         • Advantages
           • Allows inexpensive LANs to be set up without cables
           • Allows people the freedom of working anywhere a signal can be received
           • Ideal for networks in old listed buildings where cables would not be able to be installed
           • Global set of standards - you can use wifi all over the world
         • Disadvantages
           • Power consumption is high - laptops soon exhaust their rechargeable batteries
           • May be health problems in using wifi
           • There may be security problems even when encryption is used
           • Home networks have very limited ranges
           • Can get interference if wireless network signals start to overlap