What is Star Network or Star Topology?

            In a star  network, several devices or computer are connected to one centralized computer as shown in figure. The advantage of star networks is that none of the other computer can communicate with each other if the central computer breaks down. If its is desired to transmit information from one computer to another. Only sending the details the central computer can do it, which in turn send them to the destination. A star network is used in banking sector for centralized record keeping in an on-line office environment.

           

A star network has characteristic that make it more efficient that make it more efficient that bus or token ring networks. Data exchanges are better organized and more efficient, because they are different cable, there’s risk of collision. However, this type of architecture is more expensive: it requires extra cables and a controller. To optimize the function of a network without incurring exorbitant costs, several Network Architecture can be used at the same time. Then the various networks can be linked by an inter-networks link.

            A star-network; extended out in different directions from a central location. This locations is occupied by physical equipment known as a Hub.

            Each computer is connected to the hub by its own cable segment. Only a single computer can transmit at a time and every computer on the network will examine the data to see if it is meant for them. Because of the star network is made up of single device attached to the end of single cables a break in the cable affects only the device attached to that cable. Failure of a single node will not affect the rest of the network. If, however the central hub fails the entire network will go down.

            Star topology can be implemented as a passive or an active design depending on the type of Hub. A passive hub is often utilized for small networks. All data received by a passive Hub is passed directly to all computers connected to the Hub. An active Hub, amplifies incoming signals before transmitting them to the other computers.