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Ð ÐIf one workstation fails, the entire network fails.

              Ð ÐIt is quite costly.
              Ð ÐIn this network, adding and removing nodes is difficult and can cause problems with network activities.
              Ð ÐThe ring is difficult to debug.
              Ð ÐAll computers must be turned on in order for them to connect with one another.
              Star Topology

              A star topology for a LAN is one in which each node is connected to a central connection point, such as a hub or switch.
              A star requires more cable than, say, a bus, but the benefit is that if one cable fails, only one node is affected. Each
              device in the network is connected to a hub, which is a central device. If one device wishes to send information to
              another, it must first send the information to the hub, which then sends the information to the specified device.

                                                                        Device 1





                                       Device 5                                        Device 2




                                                                  Hub



                                                               Device 4          Device 3


              Advantages

              Ð ÐIt is extremely dependable; if one cable or device breaks, the others will continue to function.
              Ð ÐIt is efficient since no data collisions can occur.
              Ð ÐRobust in nature and is easier to implement.

              Ð ÐFault detection is simple.
              Ð ÐWhen attaching or disconnecting devices, there are no network interruptions.
              Ð ÐEach device only needs one port to connect to the hub.
              Ð ÐWhen N devices are connected in a star, the number of wires necessary to connect them is N. As a result, lining up
                 is simple.

              Disadvantages
               ÐMore cable is required than with a linear bus.
              Ð
              Ð ÐNodes associated with the connecting network device (network switch) are disabled and unable to communicate
                 with the network.
              Ð ÐDue to the value of the connected devices, it is more expensive than a linear bus topology (network switches)
              Ð ÐIf the hub fails, the entire system fails, and none of the devices can function without it.

              Ð ÐThe hub necessitates greater resources and regular upkeep.
              Ð ÐExtra hardware (hubs or switches) is required, which increases the cost.
              Ð ÐThe performance is based on a single concentrator, the hub.




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