2.2 Star Topology

Star Topology

Star Topology

A star topology is a topology for a Local Area Network (LAN) in which all nodes are individually connected to a central connection point, like a hub or a switch. A star takes more cable than e.g. a bus, but the benefit is that if a cable fails, only one node will be brought down.

All traffic emanates from the hub of the star. The central site is in control of all the nodes attached to it. The central hub is usually a fast, self contained computer and is responsible for routing all traffic to other nodes.

The main advantages of a star network is that one malfunctioning node does not affect the rest of the network. However this type of network can be prone to bottleneck and failure problems at the central site.

A star network is often combined with a bus topology. The central hub is then connected to the backbone of the bus. This combination is called a tree.

Advantages

1. It is very easy to install and manage star network topology as it is the simplest of the lot when it comes to functionality.
2. It is easy to troubleshoot this network type as all computers are dependent on the central hub which invariably means that any problem which leaves the network inoperable can be traced to the central hub.
3. In star topology, the data packets don't have to make their way through various nodes which makes sure that the data transfer is fast.
4. At the same time, the fact that the data packets only make it through three different points ensures that the data is safe.
5. As the nodes are not connected to each other, any problem in one node doesn't hamper the performance of other nodes in the network.
6. Adding new machines or replacing the old ones is a lot easy in this network topology, as disruption of the entire network is not required to facilitate the same.

Disadvantages

1. The foremost problem with star network topology is the fact that it is highly dependent on the functioning of central hub.
2. The size of the network is dependent on how many connections can be made to the hub.
3. This network type requires more cable as compared to linear bus topology which means the expenses incurred would be relatively high.
4. The performance of the entire network is directly dependent on the performance of the hub. If the server is slow, it will cause the entire network to slow down.
5. If one of the numerous nodes utilizes a significant portion of the central hub's processing capability, it will reflect on the performance of other nodes.