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Star network topologies are used in many networks, large and small.

In a star network topology all nodes connect to each other indirectly through one or more switches or hubs. The switch acts as a central point through which all communications are passed.

Large networks using a star network topology are usually controlled by one or more servers. Hence, the client-server model usually uses a star topology. However, peer-to-peer networks can also have a star network topology. Even though no single computer controls the network, all communications still pass through the central switch or hub.

Advantages and disadvantages of using a star network topology

Having nodes arranged in a star network topology brings some benefits:

• each node is separately connected and therefore a failure of one node or its link does not affect any other nodes
• new nodes can be added to the network simply by connecting them to the switch
• star network topologies tend to have higher performance as a message is passed on to its intended recipient only

However, star network topologies also have disadvantages:

• the whole network fails if the switch fails, as no node can communicate
• a wired star network topology requires plenty of cable - in a large network this can be expensive
• bottlenecking can occur if too much traffic passes through the central switch, making the network slow

Star network topologies in use

Star network topologies tend to be found in large organisations, such as educational establishments and businesses, where high performance is a must.

They are also found in home networks, especially those that are wireless. In this case, a router with a wireless access point (WAP) provides the central connection for all nodes.