In the previous sections, we talked about the different types of network. Network topologies describe the shape of the network which can be different depending on what the network is used for.
The shape of the network can be either physical or logical:
- Physical – the way in which the devices are set out in the building
- logical – the way in which the decives communicate
Before studying the different types of topology, make sure that you are familiar with the key terms & hardware for networks.
A Bus network has a central cable that runs the length of the whole network, called the network backbone. This cable carries the data packets between the nodes on the network.
At each end of the backbone is a cap called a terminator. This allows data packets to bounce back along the backbone if the data packet hasn’t reached its destination. Because all data is carried along the backbone, there is a higher risk of collisions.
Star topologies are the most common type of network topology in modern networks. In a star, each node on the network has its own cable which connects it to a central node. This means if a node becomes disconnected from the network, the network can still function.
However, if the central node fails in a star, the rest of the nodes will lose connection too.
Mesh topologies are used for important networks where failure would cause risk to life or significant loss of money. Banks, hospitals, and national security are examples of places where mesh networks are used.
In a mesh topology, all nodes on the network are connected to all other nodes. This means if one node or cable becomes disconnected, the rest of the network is unaffected.