Networks
Bus, Ring, Star Networks
Bus Network
In a bus network all the workstations, servers and printers are joined to one cable (the bus). At each end of the cable a terminator is fitted to stop signals reflecting back down the bus.
Advantages
Disadvantageseasy to installif the main cable fails or gets damaged the whole network will fail
cheap to install, as it doesn’t require much cableas more workstations are connected the performance of the network will become slower because of data collisions
every workstation on the network "sees" all of the data on the network – this is a security risk
Ring Network
In a ring network each device (workstation, server, printer) is connected to two other devices, this forms a ring for the signals to travel around. Each packet of data on the network travels in one direction and each device receives each packet in turn until the destination device receives it. If one bit in the circuit brakes then the whole circuit stops and nothing works, also no one can work.
Advantage
This type of network can transfer data quickly, even if there are a large number of devices connected because the data only flows in one direction, so there won’t be any data collisions.
Disadvantage
If the main cable fails or any device is faulty then the whole network will fail
Star Network
In a star network each device on the network has its own cable that connects to a switch or hub. A hub sends every packet of data to every device, whereas a switch only sends a packet of data to the destination device.
AdvantagesDisadvantages
very reliable – if one cable or device fails then all the others will continue to workexpensive to install as this type of network uses the most cable (network cable is expensive)
high performing as no data collisions can occurextra hardware required (hubs or switches) which adds to cost
if a hub or switch fails all the devices connected to it will have no network connection