Although there are many ways to configure network components, a few of them have emerged as the most common and standard network topologies used in many different kinds of systems, especially in smaller local area networks (LANs).
In a star topology, every individual network device is connected to a central hub. This hub passes appropriate signals from one device to all of the devices in a network. The central hub may or may not perform security or filtering processes on data. More complex star topologies nest one star inside another.
In a bus topology, network components are constructed in a kind of serial pattern or "daisy-chain" where data runs from one original component to an end destination through a line of network nodes.
Like the bus topology, a ring topology also sets nodes in a serial pattern, but in this case, it completes the ring or wheel, so that data can go the whole way around the network and back to the beginning again.
In addition to these three common types of topologies, complex networks can also have combinations of topologies. One common example is the "star and bus," where individual nodes of a star network are daisy-chained into a bus structure. This allows for more complex data trajectories in a sort of tree organization, from a top-level network component, down to one that is more peripheral and may only receive, not send, data.
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