What is it?
Star, or hub-and-spoke, topology is a network topology type where each individual component is physically linked to a common central node, such as a switch or hub. A star network may comprise either wired or wireless connections. The central node functions as a server, while connected network components are clients, every one of which uses the server as an intermediary. For instance, when the central node receives data from a linked device, it can transfer this data to other linked devices.
How does it work?
In the case of an Ethernet hub as a central node, a message addressed to a particular device is broadcasted to all the connected network components. On the contrary, an Ethernet switch retransmits a message to a single, destined device.
A star topology network involves connected components isolated from each other. For that reason, a failure of a single linked device does not impact the way that the rest operates, except for disabling them to communicate with the failed device. However, the malfunction of the central node disrupts the operation of the entire network.
Additionally, this kind of typology allows for connecting new components to the network or removing existing ones.