Network Topologies - Star/Bus

Network Topologies - Star/Bus

1. Bus

   • Pros
     • The network is unaffected if a single device fails
     • Aren't dependent on a central switch to keep network working.
     • Relatively cheaper than star network
   • Cons
     • Data collisions are common. Making the network slower as data has to be resent.
     • The more devices on the network, the more likely data collisions are to happen.
       • Meaning unusable for large networks.
     • Devices must wait for the bus to be available before they can send any data.
     • If bus cable gets broken, it splits network into seperate parts. Since separated network don't havve terminators on ends, this coul break whole network.
   • All devices are connected to a single cable
     • Two terminators are placed at the ends of bus to stop data reflecting back along the bus
       • Without terminators, there would be interference and the network may become unusable.

2. Star

   • Pros
     • If one device fails the rest of the network is unaffected.
     • It's simple to add more devices to network.
     • Tend to have better performance than other setups.
     • There are very few data collisions
     • All devices can transmit data at the same time
   • Cons
     • Expensive as every device needs a seperate cable
     • Switch itself is also expensive
     • If there's a problem with switch/server then whole network is affected
     • Maximum number of possible connections to network is determinedby switch.
       • If you need more connections, may have to buy additional switch
   • A star topology is where all the devices are connected to a central switch or server that controls the network.
     • The central switch allows many devices to access the server simultaneously.
     • Star networks can be wired or wireless.